Similar to the proposed approach for BEV and FCEV useful life
periods, described in IV.A, we are proposing in 40 CFR 1037.120(b)(2)
that BEV and FCEV manufacturers apply the warranty periods
corresponding to an engine-based primary intended service class, as
specified in the proposed 40 CFR 1037.120(b).487 488 The
proposed 40 CFR 1037.120(b)(2) specifies that prior to MY 2027
manufacturers choosing to generate NOX emission credits in
MYs 2024 through 2026 would apply the warranty periods in the current
40 CFR 86.001-2; starting in MY 2027 manufacturers would apply the
warranty periods specified in the proposed 40 CFR 1036.104.
Manufacturers choosing not to generate NOX emission credits
with their BEVs or FCEVs could alternatively choose in MY 2027 or later
to certify to the existing emission warranty requirements for GHGs, as
specified in the current 40 CFR 1037.120(b)(1).\489\ As specified in
the existing 40 CFR 1037.120(e), all manufacturers would continue to
describe in their owners' manual the warranty provisions that apply to
the vehicle.
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    \487\ Manufacturers would identify a primary intended service
class as specified in proposed 40 CFR 1037.102(b)(1).
    \488\ The warranty periods included in the Alternative would
similarly apply to BEVs and FCEVs; see Section IV.B.1.vi for more
discussion on the Alternative warranty periods considered for this
proposal.
    \489\ Prior to MY 2027, manufacturers who chose not to generate
NOX emission credits would apply the warranty periods
specified in the current 40 CFR 86.001-2, which are equivalent to
those specified in the current 40 CFR 1037.120(b)(1).
---------------------------------------------------------------------------

    As discussed in Section IV.A, data from BEV transit buses and DOE
research and development work on FCEVs suggest that BEV and FCEV
technologies will be capable of operating over mileages or time periods
similar to CI engines in the 2027 and beyond timeframe; thus, we
believe it is appropriate for the same criteria pollutant warranty
requirements to apply to BEV and FCEV technologies as those specified
for CI engines for those manufacturers who choose to generate
NOX emission credits.
    We further recognize that repeated repair or maintenance issues
with a BEV or FCEV could increase vehicle operating costs and lead
owners to purchase a vehicle powered by a CI or SI engine instead,
which would result in higher emissions than a zero-emission tailpipe
battery or fuel cell electric vehicle. Our proposed BEV and FCEV
warranty requirements for manufacturers who choose to generate
NOX emission credits from BEVs or FCEVs are expected to
decrease those operating costs in two ways. First, by encouraging
owners to conduct vehicle maintenance that ensures continued warranty
coverage and maintains the benefits of the zero-tailpipe emission
performance. Second, by encouraging manufacturers to simplify repair
processes and provide better training to technicians in an effort to
reduce their warranty repair costs.
    As specified in the proposed 40 CFR 1037.120(c), we propose to
clarify that batteries and fuel cells in BEVs and FCEVs, respectively,
are considered covered components and would be subject to the proposed
warranty requirements in 40 CFR 1037.120(b)(2) for manufacturers
choosing to generate NOX emission credits. Our proposed
approach for component coverage reflects that defects or failures of
batteries or fuel cells could render the vehicle inoperable, and thus
the vehicle would cease to provide zero tailpipe emission performance
over the full useful life period despite having generated emission
credits for the full useful life period. We note that our proposed
approach is less comprehensive than the CARB Zero Emission Powertrain
(``ZEP'') Certification approach, which defines ``warranted part'' as
``any powertrain component'' in the case of zero-emission
powertrains.\490\ At the end of this subsection we request comment on
our proposed approach for component coverage relative to the CARB ZEP
Certification approach.
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    \490\ See Attachment C, ``Proposed, California Standards and
Test Procedures for New 2020 and Subsequent Model Heavy-Duty Zero-
Emissions Powertrains'', p. 17 for details on warranty requirements.
Available at: https://ww2.arb.ca.gov/sites/default/files/barcu/regact/2019/zepcert/15dayattc.pdf (last accessed August 24, 2021).
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    In developing our proposal for the duration of the warranty period
for BEVs and FCEVs, we considered two other options: (1) Align with
CARB Omnibus emission warranty requirements for BEVs and FCEVs of 3
years or 50,000 miles, or (2) align criteria pollutant warranty periods
with the periods specified for GHG emissions in the current 40 CFR
1037.120 for all manufacturers. The CARB Omnibus warranty requirements
for BEVs and FCEVs match what manufacturers are already required to
offer if they participate in the California Heavy-duty Vehicle
Incentive Program (HVIP), and are less than industry standards for
warranty periods based on information submitted to CARB through the
certification process.\491\ The second option we considered, aligning
criteria pollutant and GHG warranty periods for BEVs and FCEVs would be
a simplistic approach, but would not recognize the use of these
technologies to generate NOX emission credits; under the
proposed ABT program, we would allow these NOX emission
credits to be used to produce higher-emitting engines with longer
warranty period requirements.\492\ As such we are proposing that only
manufacturers who choose not to generate NOX emission
credits with BEVs or FCEVs could choose to certify to criteria
pollutant warranty requirements equivalent to the existing GHG emission
warranty requirements.
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    \491\ California Air Resources Board, Staff Report: Initial
Statement of Reasons for Proposed Alternative Certification
Requirements and Test Procedures for Heavy-Duty Electric and Fuel
Cell Vehicles and Proposed Standards and Test Procedures for Zero-
Emission Powertrains (Zero-Emission Powertrain Certification
Regulation), December 31, 2018. Available online: https://ww3.arb.ca.gov/regact/2019/zepcert/isor.pdf.
    \492\ See Section IV.G for details on the proposed ABT program,
which includes restrictions for the extent to which engines could
emit emissions above the proposed standards.
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    We request comment on our proposed approach for BEV and FCEV
warranty requirements to match those of the engine-based primary
intended service class for manufacturers who choose to generate
NOX emission credits from BEVs or FCEVs. Commenters are
encouraged to provide information and data on whether such requirements
would help to ensure the zero-emission tailpipe performance of these
technologies, or if they would hinder the integration of these
technologies

into the heavy-duty vehicle market. If commenters suggest that we
should finalize another alternative to our proposed approach, then we
request information and data supporting their views on how such an
alternative would support the environmental benefits of zero-emission
tailpipe technologies. We further request comment on our proposed
approach that batteries and fuel cells in BEVs and FCEVs, respectively,
are covered under warranty for manufacturers choosing to generate
NOX emission credits. If commenters suggest that we include
additional components in the final rule, such as the CARB ZEP
Certification approach, we request that commenters provide a list of
which specific components should be covered (e.g., electric motor,
axles), along with a rationale for why those components should be
covered under emission warranty.
c. Proposed Warranty for Incomplete Vehicle Refueling Emission
Standards
    As noted in Section III.E, proposed Options 1 and 2 include
refueling emission standards for Spark-ignition HDE that are certified
as incomplete vehicles above 14,000 lb GVWR.\493\ Our proposed
refueling standards are equivalent to the refueling standards that are
in effect for light- and heavy-duty complete Spark-ignition HDVs. We
project manufacturers would adapt the existing onboard refueling vapor
recovery (ORVR) systems from those complete vehicle systems to meet our
proposed refueling standards.
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    \493\ See our proposed updates to 40 CFR 1037.103.
---------------------------------------------------------------------------

    As noted in Section III.E, we are not reopening or proposing to
change evaporative emission requirements that currently apply for all
SI engines or refueling emission standards that currently apply for
complete vehicles. Because the onboard refueling vapor recovery systems
necessary to meet the proposed refueling standards are expected to
build on existing evaporative systems, proposed Options 1 and 2 would
require that Spark-ignition HDE manufacturers provide a warranty for
the ORVR systems of incomplete vehicles above 14,000 lb GVWR for the
same warranty periods that currently apply for evaporative emission
control components on these vehicles.\494\ Our proposal to apply the
existing warranty periods for evaporative emission control systems to
the ORVR systems is similar to our approach to the regulatory useful
life periods associated with our proposed refueling standards discussed
in Section IV.A.
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    \494\ Warranty periods for refueling emissions components on
incomplete Light HDV would be 5 years or 50,000 miles, and 5 years
or 100,000 miles for components on incomplete Medium HDV and Heavy
HDV. See our proposed updates to 40 CFR 1037.120.
---------------------------------------------------------------------------

v. Additional Considerations for Components Covered and Warranty Claims
    Consistent with existing regulations, our proposed warranty
provisions in new 40 CFR 1036.120(c) identify the components covered by
emission warranty as the general emission-related components listed in
40 CFR 1068, appendix A, and any other components a manufacturer may
develop to control emissions. The emission-related components listed in
appendix A are broad categories of components and systems that affect
emissions. We request comment on the completeness of this list and
whether we should consider adding other systems or more specific
components of systems.
    As mentioned in Section IV.B.1.iii, CARB recently expanded their
list of components covered by emission warranty to include any
component whose failure causes the vehicle's OBD MIL to illuminate to
ensure malfunctioning components were repaired in a timely manner.\495\
We believe the proposed lengthened warranty periods would effectively
encourage prompt maintenance without the need to expand the list of
components covered beyond those specifically identified as emission-
related components. We are also including several other proposed
updates to improve access to valuable maintenance information for
certain emission-related components. We are proposing to require
manufacturers to update their owner's manuals to improve serviceability
(Section IV.B.3) and to expand the list of OBD parameters available to
the public (Section IV.C).
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    \495\ California Air Resources Board. Staff Report: Initial
Statement of Reasons-Public Hearing to Consider the Proposed Heavy-
Duty Engine and Vehicle Omnibus Regulation and Associated
Amendments. June 23, 2020. Page III-52. Available online: https://ww2.arb.ca.gov/sites/default/files/barcu/regact/2020/hdomnibuslownox/isor.pdf.
---------------------------------------------------------------------------

    As specified in the current 40 CFR 1068.115 and referenced in
proposed 40 CFR 1036.120(d), manufacturers may deny warranty claims if
the engine was improperly maintained or used. In proposed 40 CFR
1036.125(h)(2), manufacturers would describe the documentation they
require for owners to demonstrate their engines are properly
maintained.\496\ ANPR commenters suggest that DEF quality sensor data
alone is an incomplete indicator of an owner's commitment to
maintaining high-quality DEF. EPA received comments describing
incidents where DEF quality faults were triggered repeatedly despite
flushing the system and filling the tank with new DEF, suggesting a
fault with a system sensor.\497\ A recent online discussion indicates
that some OEMs may be denying warranty claims on the basis of using
poor quality DEF.\498\ While this may be justified for repeated DEF
quality faults or extremely low urea concentrations (e.g., using
water), DEF quality sensor readings may also indicate only slightly
abnormal urea concentrations due to unintentionally long storage
periods or unpredicted improper storage temperatures. In either case,
we expect a DEF quality-triggered engine derate would induce a user to
address the DEF quality issue before it would cause a problem
downstream.
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    \496\ See our discussion in Section IV.B.5.
    \497\ See the comments of the National Association of Small
Trucking Companies (``NASTC''), EPA-HQ-OAR-2019-0055-0456.
    \498\ Wallace, Sam. ``Keep Your Diesel Exhaust Fluid From
Voiding Your Warranty'', Mitchell1 ShopConnection, August, 2015.
Available online: https://mitchell1.com/shopconnection/keep-your-diesel-exhaust-fluid-from-voiding-your-warranty/.
---------------------------------------------------------------------------

    We note that current 40 CFR 1068.115 allows manufacturers to deny a
warranty claim only if they show that a component failure was due to
improper maintenance or use by the owner or operator, by accidents for
which the manufacturer has no responsibility, or by acts of God subject
to certain limitations. For example, 40 CFR 1068.115(b)(3) does not
allow a manufacturer to deny a warranty claim based on action or
inaction by the operator unrelated to the warranty claim. In proposed
40 CFR 1036.120(d), we propose to further clarify that, as described in
40 CFR 1068.115, for highway heavy-duty engines a manufacturer may deny
warranty claims if the operator caused the problem through improper
maintenance or use. In other words, a manufacturer must use more than
just the presence of a system fault before denying a warranty claim for
improper maintenance and would have to show that a component failure
was directly connected to that fault. We request comment on the
availability of high-quality DEF and whether EPA should explicitly
state that manufacturers cannot deny warranty claims based on the use
of commonly available DEF, as is currently specified for fuel in 40 CFR
1068.115(b)(6). Commenters are encouraged to suggest if a commonly
available DEF provision should be limited to heavy-duty highway engines
in 40 CFR 1036.120 or

if it should be broadly applied to all sectors covered under part 1068.
vi. Analysis of Proposed Emission Warranty Periods and Alternatives
    Consistent with our useful life discussion in Section IV.A.4, we
considered an alternative set of warranty periods (the Alternative)
that would apply as a single step beginning in model year 2027. The
warranty mileages for the Alternative are longer than the proposed
Option 1 MY 2031 useful life mileages. The Alternative mileages align
with the warranty mileages presented in CARB's September 2019 Public
Workshop for their Heavy-Duty Low NOX program and cover up
to 94 percent of the useful life mileages considered for the
Alternative.\499\ The warranty mileages of the Alternative would place
an even greater emphasis on the importance of holding manufacturers
responsible for emission control defects for a period of time that
aligns more closely with the operational life of the engine. However,
we believe it would be inappropriate to consider warranty mileages
equal to or beyond the proposed Option 1 MY 2031 useful life mileages,
which are the maximum useful life mileages we consider to be feasible
given the level of emission standards evaluated in this proposal based
on available data.
---------------------------------------------------------------------------

    \499\ Brakora, Jessica. Memorandum to Docket: EPA-HQ-OAR-2019-
0055. CARB 2019 Public Workshop Presentations Related to Regulatory
Useful Life and Emissions Warranty. March 19, 2021.

                             Table IV-10--Comparison of Warranty Mileages Considered
----------------------------------------------------------------------------------------------------------------
                                                        Proposed  Option 1
 Primary intended service class       Current    --------------------------------    Proposed       Alternative
                                                   MY 2027-2030      MY 2031+        Option 1
----------------------------------------------------------------------------------------------------------------
Spark-Ignition HDE..............          50,000         110,000         160,000         110,000         200,000
Light HDE.......................          50,000         150,000         210,000         110,000         280,000
Medium HDE......................         100,000         220,000         280,000         150,000         360,000
Heavy HDE.......................         100,000         450,000         600,000         350,000         800,000
----------------------------------------------------------------------------------------------------------------

    The Alternative warranty mileages are equivalent to or longer than
the useful life mileages included in the proposed Options 1 and 2.
Since we do not believe that the emission warranty period should be
equal to or greater than the useful life period, we focus on the
warranty values of proposed Options 1 and 2 and the range in between
them for this proposal. We expect that we would need additional data
before we could project that the standards and useful life values of
the Alternative are feasible for the MY 2027 timeframe in order to
consider adopting them, or the Alternative warranty mileages, in the
final rule.
    We estimated the emissions impacts of the Alternative warranty
periods in our inventory analysis, which is summarized in Section VI
and discussed in detail in Chapter 5 of our draft RIA. We do not
present an analysis of the costs of the Alternative, since those
warranty periods are out of the range of mileages we are currently
considering without additional information to indicate that the
standards and useful life values of the Alternative are feasible in the
MY 2027 timeframe.
vii. Other Approaches To Ensure Long-Term In-Use Emission Performance
    Under our current and proposed warranty provisions, parts and labor
for emission-related components are equally and fully covered over the
entirety of the warranty period. A graduated warranty coverage
approach, which was introduced as a topic in the ANPR to this rule and
is described in more detail below, may provide a similar assurance of
long-term emission performance with a smaller impact on the purchase
price.
    Manufacturers are responsible for repairing or replacing emission-
related components that are found to be defective within the specified
warranty period. Manufacturers include warranty repairs in the price of
an engine or vehicle, and the Agency considers the warranty cost
implications of all our emission control rules.\500\ In Section V, we
provide the cost impacts of the proposed warranty periods. The impact
that a longer warranty would have on the purchase price of an
individual engine will vary by factors such as a manufacturer's
estimate of the risk for an engine, their presumed competition in the
market, and their relationship with the purchaser.
---------------------------------------------------------------------------

    \500\ A manufacturer estimates the expected costs of warranty
repairs actuarially, and these costs are added to the purchase price
of the engine or vehicle, spreading the predicted repair costs over
the number of engines or vehicles sold.
---------------------------------------------------------------------------

    In the current market, purchasers desiring greater warranty
protection can buy extended warranties, either from the engine
manufacturers or third-party companies. The experience with extended
warranties reveals information about the range of owner preferences
with respect to bearing the costs of out-of-warranty repairs. Some of
the estimated 40 percent of purchasers obtaining extended warranties
may be large companies that purchase extended warranty coverage because
they have comprehensive in-house service facilities and a business
relationship with engine manufacturers that allows them to perform
warranty repairs in-house. Other owners may be reliant on the engine
manufacturer for warranty repairs but prefer to purchase extended
warranties for insurance against the cost of out-of-warranty repairs,
in essence paying for those repairs up-front. Of the 60 percent of
purchasers that decline to purchase extended warranties, some companies
may reduce the risk of out-of-warranty repair costs by selling their
vehicles near the point when the warranty period ends. Others may
prefer to pay for out-of-warranty repairs when and if they occur. Still
others may choose to not make out-of-warranty repairs at all. It is
clear that lengthening the warranty period would remove some of a
purchaser's flexibility to address out-of-warranty repair costs. We
request comment on the extent to which emissions warranty period is an
important aspect of purchasers' business decisions, and the specific
impacts purchasers anticipate for the range of emissions warranty
periods we are considering in this rule. For instance, we are
interested in how a longer regulatory emissions warranty may impact the
timing of an engine or truck purchase, how long an engine or vehicle is
kept, and/or how well an engine is maintained.

    In the ANPR, we described two different potential approaches to
graduated warranties. Under one approach, there could be longer,
prorated warranties that provide different levels of warranty coverage
based on a vehicle's age or mileage. Alternatively, the warranty could
be limited to include only certain parts during specified warranty
periods, and/or exclude labor for some, or even all, of the duration of
coverage. We received feedback from several stakeholders in response to
the ANPR. Allison Transmission supported EPA considering prorated parts
and labor as an approach to lengthening warranty periods.\501\ Volvo
suggested that applying the longer warranty periods to only critical
components could be a way to reduce manufacturer costs.\502\ NADA
recommended that longer warranty periods be proposed in a manner that
varies by class of component or system and include the approaches EPA
presented in the ANPR such as limited component and/or prorated
warranties.\503\
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    \501\ See comments from Allison, Docket ID EPA-HQ-OAR-2019-0055-
0461.
    \502\ See comments from Volvo, Docket ID EPA-HQ-OAR-2019-0055-
0463.
    \503\ See comments from NADA, Docket ID EPA-HQ-OAR-2019-0055-
0369.
---------------------------------------------------------------------------

    We are not proposing and did not analyze a graduated warranty
approach for this proposal. However, we may consider a graduated
warranty as a viable alternative to our proposed warranty periods if we
receive additional information that would support such an approach. A
graduated warranty approach could extend beyond our proposed warranty
periods in mileage, hours, and years, to cover more of the operational
life of the engine, but it could be based on different phases of
varying coverage. These could include, for example:
     Phase 1: Full parts and labor coverage for all emission-
related components,
     Phase 2: Parts and labor coverage for limited emission-
related components, and
     Phase 3: Parts-only coverage for limited emission-related
components.
    We request comment on whether EPA should adopt a phased approach
for a longer emission warranty period. Supporters of such an approach
should comment on the number of phases, the length of each phase, and
the components to include in the set of limited emission-related
components under such an approach. With respect to Phase 1, which would
be similar to a traditional warranty with full parts and labor
coverage, EPA may consider the warranty mileages in proposed Option 2
as the minimum lower bound. For the other phases, commenters are
encouraged to include data to support their suggested mileage, hours,
and years of coverage. When considering the set of limited parts to be
covered in the other phase(s), EPA may consider including components
that are relatively high-cost components, or components that are labor-
intensive (and thus expensive) to replace. We request data to support
the set of limited emission-related components that should be included
in the other phase(s), including failure rates, component costs, and
labor costs to replace specific components. We note that our proposed
maintenance provisions in 40 CFR 1036.125 include two categories of
components we could consider as the set of limited emission-related
components covered in the graduated warranty approach. As described in
Section IV.B.5, these two categories of components include a proposed
list of specific components with minimum maintenance intervals, and
criteria to identify components that can only be replaced as part of
scheduled maintenance if the manufacturer covers the cost.
    Finally, we request comment on whether a graduated warranty
approach would achieve the goals set out in Section IV.B.1.ii:
Providing an extended period of protection for purchasers, encouraging
proper maintenance, discouraging tampering, and incentivizing
manufacturers to design emission control components that are less
costly to repair.
2. Electronic Control Module Security
    CAA section 203(a)(3)(B) and 40 CFR 1068.101(b)(2) prohibit
selling, offering to sell, or installing any part or component whose
principal effect is to bypass, defeat, or render inoperative a motor
vehicle emission control device or element of design (i.e., a ``defeat
device''), where the person knows or should know that the part is being
offered for sale, installed for such use or put to such use. Once
installed, defeat devices can result in significant tailpipe emissions
increases, and with the long service life of heavy-duty vehicles, would
produce a disproportionate amount of lifetime emissions, compared to a
vehicle with properly functioning emission controls. One of the key
enablers of defeat devices with modern engines is the unauthorized
modification, or tampering, with certified calibration parameters and/
or software within the electronic control module (``ECM''). Tampering
with the ECM can introduce a different calibration that allows the
engine to produce power at higher emission rates, or it can bypass or
disable inducement algorithms intended to ensure proper functioning of
SCR systems. The EPA Office of Enforcement and Compliance Assurance
(OECA) has found extensive evidence of tampering with the emission
control systems on heavy-duty engines and vehicles nationwide, although
EPA lacks robust data on the exact rate of tampering.\504\ Recently,
OECA announced a new National Compliance Initiative (``NCI'') to
address the manufacture, sale, and installation of defeat devices on
vehicles and engines through civil enforcement.\505\
---------------------------------------------------------------------------

    \504\ U.S. EPA. ``Tampered Diesel Pickup Trucks: A Review of
Aggregated Evidence from EPA Civil Enforcement Investigations'',
November 20, 2021, Available online: https://www.epa.gov/enforcement/tampered-diesel-pickup-trucks-review-aggregated-evidence-epa-civil-enforcement.
    \505\ U.S. EPA. National Compliance Initiative: Stopping
Aftermarket Defeat Devices for Vehicles and Engines. Available
online: https://www.epa.gov/enforcement/national-compliance-initiative-stopping-aftermarket-defeat-devices-vehicles-and-engines.
---------------------------------------------------------------------------

    EPA has for decades had regulations to address the ``physically
adjustable parameters'' on heavy-duty highway engines that can alter
emissions performance.\506\ These regulations require the manufacturer,
subject to review by EPA, to identify the appropriate range of
adjustment on the operating parameters or physical settings on an
engine that could potentially increase emissions and the adequacy of
limits, stops, seals, or other mechanical means of limiting or
prohibiting adjustment outside of these appropriate ranges. Parameters
such as injection timing on a diesel engine were once physically
adjustable with common tools and clearly an adjustable parameter. With
a modern ECM, many of these parameters are now electronically
adjustable through changes to software and calibration settings. As
discussed in Section XII.A.2, we are proposing to revise our
regulations by adding 40 CFR 1068.50 to specifically address
electronically adjustable parameters and require that manufacturers
attest that they are using sufficient measures to secure the ECM,
thereby limiting adjustment or alteration beyond those used in the
certified configuration.
---------------------------------------------------------------------------

    \506\ 40 CFR 86.094-22.
---------------------------------------------------------------------------

    ECM tampering is often designed to avoid detection, where the
software, controls, and onboard diagnostics are intentionally
manipulated so commonly available scan tools cannot detect the presence
of a defeat device. This complicates the efforts of state

inspection and maintenance programs to identify and address tampered
vehicles. ECM tampering is also a concern for manufacturers, because
changes to the engine controls can adversely impact the durability of
the engine and lead to premature failure. If ECM tampering remains
undetected and a failure occurs within the warranty period, the
manufacturer would be responsible for the repair costs. Manufacturers
have been implementing measures to prevent tampering with software in
the engine's ECM, but manufacturers of defeat devices continue to find
ways to work around these security measures. Unauthorized access to the
ECM and other control modules on a vehicle is also a public safety
concern, as malicious tampering could affect the operation of the
advanced braking, stability, and cruise control systems found on modern
heavy-duty vehicles.\507\
---------------------------------------------------------------------------

    \507\ Stachowski, S., Bielawski, R., Weimerskirch, A.
Cybersecurity Research Considerations for Heavy Vehicles (Report No.
DOT HS 812 636). Washington, DC: National Highway Traffic Safety
Administration. December 2018.
---------------------------------------------------------------------------

    To address the safety, financial liability, operational, and
privacy concerns that can result from tampering, manufacturers,
industry organizations, and regulators have been working to develop
standards and design principles that would improve vehicle
cybersecurity, including ECMs. Three such efforts where cybersecurity
guidelines and procedures are either under development or already in
publication are ISO/SAE J21434, UNECE WP29 Cybersecurity Regulation,
and SAE J3061.508 509 \510\ Manufacturers may choose to
utilize different mixes of technical standards or principles that these
organizations recommend. A one-size-fits-all approach with detailed
requirements for ECM security for all engines would be neither
practical nor prudent. Manufacturers need the flexibility to quickly
implement measures to address new or emerging threats and
vulnerabilities. Considering this need for flexibility and noting that
the security principles in these efforts are constantly evolving as new
threats are identified, we are not proposing to adopt any of these
specific guidelines as requirements for manufacturers.
---------------------------------------------------------------------------

    \508\ ``Road vehicles -- Cybersecurity engineering``, ISO/SAE
FDIS 21434, https://www.iso.org/standard/70918.html.
    \509\ United Nations Economic Commission for Europe, ``UNECE
WP29 Automotive Cybersecurity Regulation'', Available online:
https://argus-sec.com/unece-wp29-automotive-cybersecurity-regulation/.
    \510\ Society of Automotive Engineers, ``Cybersecurity Guidebook
for Cyber-Physical Vehicle Systems``. SAE J3061, Available online:
https://www.sae.org/standards/content/j3061_201601/.
---------------------------------------------------------------------------

    In 40 CFR 1036.205(s), we propose that manufacturers describe all
adjustable parameters in their application for certification, which
would include electronically controlled parameters. Electronically
controlled parameters may be considered practically adjustable as
described in proposed 40 CFR 1068.50(d)(2). This would include user-
selectable operating modes and modifications that owners can make with
available tools. We are proposing that manufacturers describe their
approach to limiting access to electronic controls in the certification
application. We retain the right to evaluate a manufacturer's
determination in their application considering the measures they are
using (whether proprietary standards, industry technical standards, or
a combination of both), to prevent access to the ECM. At a minimum,
this documentation should describe in sufficient detail the measures
that a manufacturer has used to: prevent unauthorized access; ensure
that calibration values, software, or diagnostic features cannot be
modified or disabled; and respond to repeated, unauthorized attempts at
reprogramming or tampering.\511\ Section XII.A.2 of this preamble
describes our proposed new section 40 CFR 1068.50 to codify a set of
provisions that are consistent with current industry best practices
with respect to adjustable parameters. Additional discussion can be
found in Chapter 2 of the draft RIA.
---------------------------------------------------------------------------

    \511\ We are proposing that engines are not in the certified
configuration if they are produced with adjustable parameters set
outside the range specified in their application for certification
or produced with other operating parameters that do not conform to
the certified configuration. See Section XII and proposed 40 CFR
1068.50(i).
---------------------------------------------------------------------------

3. Serviceability
    Defective designs and tampering can contribute significantly to
increased in-use emissions. EPA has warranty provisions and tampering
prohibitions in place to address such issues. Mal-maintenance, which
includes delayed or improper repairs and delayed or unperformed
maintenance, also increases in-use emissions and can be intentional
(e.g., deferring repairs due to costs) or unintentional (e.g., not
being able to diagnose the actual problem and make the proper repair).
Mal-maintenance (by owners or repair facilities) can result from:
     Difficulty and high costs to diagnose and repair
     Inadequate troubleshooting guides and maintenance
instructions
     Limited access to maintenance information and specialized
tools to make repairs
    Vehicle owners, repair technicians, and manufacturers all play
important and distinct roles in achieving intended in-use emission
system performance and preventing mal-maintenance. Vehicle owners are
expected to properly maintain the engines, which includes performing
preventative maintenance, scheduled maintenance (e.g., maintaining
adequate DEF supply for their diesel engines' aftertreatment), and
completing repairs when components or systems degrade or fail. Repair
technicians are expected to properly diagnose and repair malfunctioning
emission systems. Finally, manufacturers play a key role in providing
both owners and repair technicians with access to the information they
need to perform such expected maintenance and repairs.
    EPA published several rules between 1993 and 2003 that improved
service information access and required onboard diagnostic (OBD)
systems for light-duty vehicles up to 14,000 lb GVWR.\512\ In 2009, EPA
finalized similar requirements for the heavy-duty industry to ensure
that manufacturers make diagnostic and service information available to
any person repairing or servicing heavy-duty vehicles and engines (74
FR 8309, February 24, 2009).\513\ The service information requirements
include information necessary to make use of the OBD system and
instructions for making emission-related diagnoses and repairs,
training access, technical service bulletins, and other information
generally available to their franchised dealers or other persons
engaged in the repair, diagnosing or servicing of motor vehicles. Since
this time, manufacturers have entered into a service-related agreement
through trade associations representing the aftertreatment repair
industry and truck and engine manufacturers, highlighting concerns over
intellectual property and their continued need for proprietary
tools.\514\ EPA is not proposing changes to service

information regulations at this time. While the service information
regulations were an important first step in improving serviceability,
as emission control systems have continued to develop, it has become
necessary to consider other improvements that can be made to support
in-use maintenance and repair practices. CAA section 207(c)(3)(A)
requires manufacturers to provide instructions for the proper
maintenance and use of a vehicle or engine by the ultimate purchaser
and requires such instructions to correspond to EPA regulations.
Section 207(c)(3)(A) also requires manufacturers to provide notice in
those instructions that maintenance, replacement, or repair of emission
control devices and systems may be performed by any automotive repair
establishment or individual using any automotive part which has been
certified as provided in section 207(a)(2). Section 207(c)(3)(B)
requires that these instructions shall not include any condition on the
ultimate purchaser's using, in connection with such vehicle or engine,
any component or service (other than a component or service provided
without charge under the terms of the purchase agreement) which is
identified by brand, trade, or corporate name; or directly or
indirectly distinguishing between service performed by the franchised
dealers of such manufacturer or any other service establishments with
which such manufacturer has a commercial relationship, and service
performed by independent automotive repair facilities with which such
manufacturer has no commercial relationship; unless EPA finds the
vehicle or engine will function properly only if the component or
service so identified is used in connection with such vehicle or
engine, and that such a waiver is in the public interest.
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    \512\ See 58 FR 9468 (February 19, 1993); 60 FR 40474 (August 9,
1995); 65 FR 59896 (Oct 6, 2000); and 68 FR 38428 (June 27, 2003).
    \513\ See 40 CFR 86.010-38(j) for the current service
information requirements. We are not proposing to migrate the
service information provisions at this time and these provisions
will remain in part 86. We are proposing to name the service
information provisions as an additional requirement in proposed 40
CFR 1036.601(b). EPA may consider migrating these provisions in a
future rulemaking.
    \514\ Memorandum of Understanding National Commercial Vehicle
Service Information. August 2015. Available online: https://www.etools.org/Heavy-Duty-MOU-2015.
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    Section 207(c)(3)(C) states that manufacturers must affix a
permanent label indicating that the vehicle or engine is covered by a
certificate of conformity and containing other information relating to
control of motor vehicle emissions as prescribed by EPA regulations.
Finally, section 202(m)(5) clarifies that manufacturers must provide
this information promptly to anyone engaged in the repairing or
servicing of motor vehicles or engines, except as specified. This
section describes proposed regulatory amendments under these statutory
provisions and are intended to improve serviceability, reduce mal-
maintenance, and ensure owners are able to maintain emission
performance throughout the entire in-use life of heavy-duty engines.
i. Current Repair and Maintenance Experiences
    Continued maintenance issues can result in, among other things,
owner dissatisfaction, which may cause some owners to remove or bypass
emission controls. Any actions we can take to reduce maintenance issues
could reduce incidents of tampering. In the ANPR, EPA requested comment
on experiences with serviceability and received comment in three
general categories: (1) Frustrations related to advanced emission
control system reliability; (2) misdiagnosis and improper repair by
professional facilities which lead to repeated trips to repair
facilities and significant downtime, and (3) limited access to
maintenance information which leads to the inability to self-diagnose
problems.
    Serviceability concerns affect all trucking operations, although
different types of operators may experience these impacts in different
ways. EPA received comments from trade organizations representing very
large trucking fleets (e.g., the American Trucking Associations,
``ATA''), small fleets (e.g., National Association of Small Trucking
Companies, ``NASTC''), and owner-operators (e.g., Owner-Operator
Independent Drivers Association, ``OOIDA''), as well as from
independent commenters, indicating that serviceability issues are one
of the top concerns when operating trucks with advanced emission
control systems. ATA commented that current emission control systems
are still causing concerns for fleets and noted that in a recent study
by ATA's Truck Maintenance Council, aftertreatment maintenance issues,
serviceability, and ease of diagnostics were identified as major areas
of concern by their members.\515\ NASTC submitted comments directly
from their members indicating a number of concerns related to
serviceability.\516\ OOIDA commented that their members have
encountered various problems with emissions systems which have had a
dramatic impact on their businesses including expensive visits to
dealers, lost productivity, poor efficiency, and towing costs.\517\ A
number of other commenters described their experiences and how
improvements can be made to reduce cost and frustration.\518\ Trucking
companies participating in a round table discussion in EPA's Region 7
expressed similar concerns about impacts to business as a result of
delayed or missed deliveries, including lost customers, and possible
legal or contract consequences.\519\
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    \515\ See the comments of the American Trucking Association,
Docket ID EPA-HQ-OAR-2019-0055-0357.
    \516\ See the comments of the National Association of Small
Trucking Companies, Docket ID EPA-HQ-OAR-2019-0055-0456.
    \517\ See the comments of the Owner-Operator Independent Drivers
Association, Docket ID EPA-HQ-OAR-2019-0055-0397.
    \518\ For example, see the comments of Swanny's Trucking, Docket
ID EPA-HQ-OAR-2019-0055-0252.
    \519\ Kopin, Amy. Memorandum to docket EPA-HQ-OAR-2019-0055.
``EPA Region 7 Heavy-Duty NOX ANPR Roundtable
Discussion--Serviceability- and Inducement-Related Concerns``.
October 1, 2021.
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    In addition to operators, EPA received comments from state and
local agencies supportive of improving access of maintenance
information and service tools for fleets and owner-
operators.520 521 For example, NACAA stated that EPA should
work to increase access to the information and tools needed to repair
the emission control systems on aging trucks, which is especially
important for small businesses, small fleets, independent owner/
operators, and rural operations, where access to dealer service
networks can be a challenge.
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    \520\ See the comments of the National Association of Clean Air
Agencies, Docket EPA-HQ-OAR-2019-0055-0283.
    \521\ See the comments of the Northeast States for Coordinated
Air Use Management, Docket EPA-HQ-OAR-2019-0055-0288.
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a. Reliability of EPA 2010 Engines
    We are keenly aware of significant discontent expressed by owners
concerning their experiences with emission systems on engines compliant
with EPA 2010 standards. EPA has also identified numerous Technical
Service Bulletins submitted by OEMs to NHTSA's website documenting
issues such as no trouble found, wiring concerns, or minor corrosion on
connectors which can lead to inducement.\522\ Although significant
improvements have been made to these systems since they were first
introduced into the market, reliability and serviceability continue to
cause concern. ATA commented that their members are experiencing
problems with a wide variety of issues such as: Aftertreatment wiring
harness failures, DEF nozzles plugging or over-injecting,
NOX sensor failures, defective DEF pumps and level sensors,
systems being less reliable in rain and cold weather, more frequent
required cleaning of DPFs, and problems related to DEF

build-up.\523\ ATA also stated that their members have reported that
mechanics at dealerships sometimes clear codes with no associated
repairs being made. Many of these issues can also lead to severe engine
derate and towing costs (see Section IV.D for further information on
proposed inducement provisions, including revisions to policy currently
in guidance). OOIDA commented that some of its members have experienced
emission technology failures that caused their engines to quickly
derate, placing truckers and other motorists in unsafe situations.\524\
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    \522\ See NHTSA Service Bulletins: ID Number 10058856, available
here: https://static.nhtsa.gov/odi/tsbs/2015/SB-;10058856-6479.pdf
and ID Number 10154333, available here: https://static.nhtsa.gov/odi/tsbs/2019/MC-10154333-9999.pdf.
    \523\ See the comments of the American Trucking Association,
Docket ID EPA-HQ-OAR-2019-0055-0357.
    \524\ See the comments of the Owner-Operator Independent Drivers
Association, Docket ID EPA-HQ-OAR-2019-0055-0397.
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    In addition to the comments highlighting problems related to wiring
harness issues and sensor failures, a number of published articles have
presented similar findings. For example, ``Dealing with Aftertreatment
Issues'' in Fleet Equipment Magazine discusses how at least one OEM is
focusing on improving issues with wiring and sensors ``which are often
the culprits in aftertreatment downtime.'' \525\ A recent article from
Transport Topics highlights how fleets are experiencing wiring issues
and sensor failures that are creating problems that even sophisticated
diagnostic tools cannot solve easily.\526\
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    \525\ Crissey, Alex. Fleet Equipment Magazine. ``Dealing with
Aftertreatment Issues''. November 27, 2017. Available online:
https://www.fleetequipmentmag.com/dealing-aftertreatment-issues/.
    \526\ Frantz, Gary. Transport Topics. ``Diesel Engine Makers
Tackle Challenges Posed by Stricter Emission Standards''. May 11,
2020. Available here: https://www.ttnews.com/articles/class-8-engine-makers-tackle-challenges-posed-stricter-emission-standards.
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b. Misdiagnosis and Improper Repairs
    Misdiagnosis can lead to the unnecessary replacement of parts
without properly addressing the problem, which can result in additional
breakdowns and tows with return trips to repair facilities for
diagnostic service. ATA commented that several fleets are reporting the
need for 'comeback' repairs and that while emissions-related training
for diagnosis and repair work has improved, it is still severely
lagging behind expectations. The NASTC describes problems some owners
have experienced with repeated emission system component failures.\527\
In one example, an owner had to replace four NOX sensors,
two diesel exhaust fluid (DEF) filters, a DEF pump, a DPF, and a diesel
oxidation catalyst (DOC) within only 6 months of purchasing a new
truck. NASTC also described problems other owners experienced due to
failures of NOX sensors, DPF filters, DOCs, other emission-
related sensors, and wiring harnesses, as well as repeated DEF doser
injector pumps and valve failures. Other NASTC commenters described
improper repair experiences resulting in trucks being down for weeks at
a time. An independent commenter stated that repeated repairs in a 6-
month time period resulted in loss of his truck and the ability to
continue as an owner-operator.\528\
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    \527\ See the comments of the National Association of Small
Trucking Companies (``NASTC''), EPA-HQ-OAR-2019-0055-0456.
    \528\ See the comments of J. Johnson, Docket ID EPA-HQ-OAR-2019-
0055-0265.
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c. Limited Access to Repair Facilities, Maintenance Information, and
Service Tools
    In response to the ANPR, EPA received numerous comments on
difficulties associated with repairs of emission control systems. Many
commenters indicated there is a substantial wait time to get a vehicle
into a specialized repair facility, which, in some cases, was more than
a week in addition to the time required to repair the vehicle.\529\
This wait time may be manageable if the vehicle remains operational,
but can have a significant impact on an owner's ability to generate
income from a vehicle if the truck is subject to an inducement and they
are unable to use the vehicle until the repair is made.\530\ EPA
received comments from the National Tribal Air Association and Keweenaw
Bay Indian Community suggesting that service information and tools are
not readily available and affordable for individual owners to diagnose
and fix their own vehicles, and improved access can be especially
important for small businesses, Tribes, and those in rural areas with
less ready access to original equipment manufacturer dealer
networks.\531\
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    \529\ See the comments of J. Sibley, Docket ID EPA-HQ-OAR-2019-
0055-0397 and those of the National Association of Small Trucking
Companies, Docket ID EPA-HQ-OAR-2019-0055-0456.
    \530\ See Section IV.D for proposed inducement provisions, which
include revisions to policy currently in guidance.
    \531\ See the comments of the National Tribal Air Association,
Docket ID EPA-HQ-OAR-2019-0055-0282.
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    EPA received a number of comments on difficulties getting the right
information or tools to repair vehicles outside of specialized repair
facilities. ATA commented that their members report that in order to
ensure proprietary tools are used, some manufacturers lock out certain
diagnostic programs needed to further diagnose and reset systems after
repairs, which ATA believes is a barrier to owners quickly diagnosing
emission control system problems. ATA added that while some large
fleets have added laptops in the field to help troubleshoot issues,
fleets with more than one brand of truck may face significant expense
to acquire multiple OEM software/diagnostic packages for these laptops.
NASTC members noted that there are very few independent repair
facilities that will repair emission systems problems, and given the
long lead times at traditional repair facilities, a single fault code
can remove a truck from service for more than a week. NASTC members
also commented that diagnostic tools for owners are not affordable but
are currently the only way to access diagnostic codes outside of a trip
to a repair facility. OOIDA commented that according to a 2018 survey,
73 percent of their members perform repairs and maintenance on their
own trucks.\532\ OOIDA added that being able to diagnose problems and
repair equipment outside of dealerships is important for owner-
operators and allows them to save time, avoid downtime, and reduce
operating costs; however, they believe that restrictions built into
existing trucks are preventing this practice. OOIDA supported an
emphasis on serviceability improvements so that professional drivers
can independently identify and repair problems with their engines and
aftertreatment as much as possible.
---------------------------------------------------------------------------

    \532\ See the comments of the Owner-Operator Independent Drivers
Association, Docket ID EPA-HQ-OAR-2019-0055-0397.
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ii. Proposed Maintenance Information for Improved Serviceability
    In addition to labeling, diagnostic, and service information
requirements, EPA is proposing to require important maintenance
information be made available in the owner's manual.\533\ The owner's
manual is a document or collection of documents prepared by the engine
or vehicle manufacturer for the owner or operator to describe
appropriate engine maintenance, applicable warranties, and any other
information related to operating or maintaining the engine or vehicle.
EPA is proposing to require additional maintenance information in the
owner's manual as a way to improve factors that may contribute to mal-
maintenance, resulting in better service experiences for independent
repair technicians,

specialized repair technicians, owners who repair their own equipment,
and possibly vehicle inspection and maintenance technicians.\534\
Combined with our proposed modifications to onboard diagnostic
requirements and proposed provisions for inducements, we expect these
proposed serviceability provisions would improve owner experiences
operating and maintaining heavy-duty engines and provide greater
assurance of long-term in-use emission reductions by reducing
likelihood of occurrences of tampering.\535\
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    \533\ Miller, Neil; Kopin, Amy. Memorandum to docket EPA-HQ-OAR-
2019-0055. ``Serviceability and Additional Maintenance
Information''. October 1, 2021.
    \534\ EPA is also proposing changes to existing useful life
periods to incentivize improved component durability (see Section
IV.A)), onboard diagnostic requirements intended to make emission
system faults more easily diagnosed (see Section IV.C), and is
proposing inducement provisions for DEF replenishment, DEF quality
and certain SCR-related tamper-resistant design intended to ensure
manufacturers can meet adjustable parameter and critical emission-
related scheduled maintenance requirements (see Section IV.D).
    \535\ See Section IV.C for discussion on proposed changes to
onboard diagnostic requirements and Section IV.D for proposed
inducement provisions.
---------------------------------------------------------------------------

    EPA is proposing changes to owner's manual and label requirements
that would be mandatory for MY 2027 and later engines. The existing
proposal would be voluntary for earlier model years, but we are seeking
comment on making all or parts of this proposal mandatory as soon as MY
2024. We expect these changes would increase owner understanding of
emission control systems, improve experiences at repair facilities,
provide better access to information to help identify concerns, and
enable owners to self-diagnose problems (especially important for aging
trucks). Our proposal is intended to ensure consistent access to
emission systems diagrams and part number information across the range
of commercial vehicle engines and improve clarity in the information
presented in those diagrams. Owner's manuals today include very
detailed descriptions of systems such as radios and infotainment
centers, fuse box and relay diagrams, and troubleshooting guides for
phone connectivity features, but generally include limited information
on emission control system operations. Given the importance and
complexity of emission control systems and the impact to drivers for
failing to maintain such systems (e.g., inducements), EPA believes
including additional information about emission control systems in the
owner's manual is critical.
    We are proposing to require manufacturers to provide more
information concerning the emission control system in both the owner's
manual and the emissions label. Our proposal would require the owner's
manual to include descriptions of how the emissions systems operate,
troubleshooting information, and diagrams. The emissions label would
include an internet link to obtain this additional information. EPA has
had similar requirements in the past, such as when EPA required vacuum
hose diagrams to be included on the emission label to improve
serviceability and help inspection and maintenance facilities identify
concerns.\536\
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    \536\ See 53 FR 7675, March 9, 1988 and 55 FR 7177, February 29.
1990 for more information.
---------------------------------------------------------------------------

    Specifically, as a part of the new 40 CFR 1036.125(h)(3)-(9) and
(11), we propose that manufacturers provide the following additional
information in the owner's manual:
     A description of how the owner can use the OBD system to
troubleshoot problems and access emission-related diagnostic
information and codes stored in onboard monitoring systems including
information about the role of the proposed health monitor to help
owners service their engines before components fail.
     A general description of how the emission control systems
operate.
     One or more diagrams of the engine and its emission-
related components with the following information:
    [cir] The flow path for intake air and exhaust gas.
    [cir] The flow path of evaporative and refueling emissions for
spark-ignition engines, and DEF for compression-ignition engines, as
applicable.
    [cir] The flow path of engine coolant if it is part of the emission
control system described in the application for certification.
    [cir] The identity, location, and arrangement of relevant sensors,
wiring, and other emission-related components in the diagram.
Terminology to identify components would be required to be consistent
with codes you use for the OBD system.
    [cir] Expected pressures at the particulate filter and exhaust
temperatures throughout the aftertreatment system.
     Exploded-view drawings to allow the owner to identify the
part numbers and basic assembly requirements for turbochargers,
aftercoolers, and all components required for proper functioning of EGR
and aftertreatment devices including enough detail to allow a mechanic
to replace any of those components.
     A basic wiring diagram for aftertreatment-related
components including enough detail to allow a mechanic to detect
improper functioning of those components.
     Statement instructing owners or service technicians where
to find emission recall and technical repair information available
without charge from the National Highway Traffic Safety
Administration.\537\
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    \537\ In 2016, NHTSA issued a Federal Register notice (81 FR
16270, March 25, 2016) stating it would post all Technical Service
Bulletins and communications to dealers on defects in vehicles,
regardless of whether the defects were safety related to comply with
the Congressional mandate in in the ``Moving Ahead for Progress in
the 21st Century Act'' (MAP-21) enacted on July 6, 2012. More
information is available here: https://www.autosafety.org/how-to-find-technical-service-bulletins-and-other-manufacturer-communications-via-nhtsas-search-portal/.
---------------------------------------------------------------------------

     Troubleshooting guide to address DEF dosing- and DPF
regeneration-related warning signals that would be displayed in the cab
or with a generic scan tool, including a description of the fault
condition, the potential causes, the remedy, and the consequence of
continuing to operate without remedy including a list of all codes that
cause derate or inducement (e.g., list SPN/FMI combinations and
associated operating restrictions, see proposed requirements in 40 CFR
1036.110(b)(9)(vi)).
     For the DPF system, instructions on how to remove DPF for
cleaning, criteria for cleaning the DPF including pressure drop across
the filter, clean filter weight, pre-installed filter weight, a
statement that DPF inlet and outlet pressures are available with a
generic scan tool, and information on maintenance practices to prevent
damage to DPFs.
    We propose to include these eight additional provisions for all
engine configurations, including hybrids, where applicable.\538\ EPA is
seeking comment on these eight proposed additional provisions or other
approaches to improve the serviceability of heavy-duty engine emission
control systems. Finally, in 40 CFR 1036.135(c), EPA is proposing that
manufacturers include a Quick Response Code or ``QR Code'' on the
emission label that would direct repair technicians, owners, and
inspection and maintenance facilities to a website which provides
critical emissions systems information at no cost including: A digital
copy of the owner's manual (or just the emissions section of the
manual), engine family information, emission control system
identification, and fuel and lubricant requirements (see proposed
revisions in 40 CFR 1036.135). Many manufacturers already make digital
owner's manuals

available online.\539\ EPA recognizes that there may be a need to
accommodate different information formats relating to the QR code link
and requests comment on whether to include different options to achieve
the same goals, and if so, what those options should be. The
maintenance information we are proposing to add to the owner's manual
is critical to making necessary information available promptly to any
person performing emissions-related maintenance.
---------------------------------------------------------------------------

    \538\ See Section IV.B.3.iii for discussion on potential
serviceability requirements for BEV and FCEV technologies on which
we are seeking comment. Section IV.I also discusses potential
maintenance requirements for manufacturers who choose to generate
NOX emission credits from BEVs or FCEVs.
    \539\ Montoya, Ronald, ``How to Find Your Car Owner's Manual
Online.'' October 18th, 2013. Available online at: https://www.edmunds.com/how-to/how-to-find-your-car-owners-manual-online.html.
---------------------------------------------------------------------------

    Including the proposed additional information in the owner's manual
and emission label can increase an owner's understanding of emission
systems operation and fault conditions. Providing owners and repair
technicians access to diagrams describing system layout and operation
can help reduce confusion where manufacturers may have different system
configurations. For example, some configurations may have the DPF in
front of the SCR catalyst, while others may have it behind the SCR
catalyst.\540\ Lack of easily accessible diagrams can lead to mal-
maintenance and improper repair where components that need to be
replaced are not identified properly. For example, some manufacturers
label exhaust gas temperature (EGT) sensors generically such as EGT1
and EGT2 and the positioning of these sensors may differ or be reversed
for the same engine model installed on vehicles with slightly different
frame configurations.\541\ If a technician is unfamiliar with this
change, they may replace the wrong EGT which would likely result in a
repeat visit to a repair facility. Similarly, a DPF temperature sensor
may be generically labeled ``Exhaust Temperature Sensor'' and may be
shown on an EGR parts diagram rather than a DPF parts diagram, making
it difficult to correctly identify replacement parts. With an easily
accessible parts diagram, owners, parts counter specialists, and repair
technicians can more quickly identify the correct parts to replace
which would save time and eliminate frustration, especially where a
truck is in an inducement. EPA is also seeking comment on the need to
require standardization of terminology for certain components in the
proposed labeling and owner's manual provisions to further reduce
confusion for owners and technicians performing repairs. For example,
some manufacturers call the DOC outlet temperature a DPF inlet
temperature. Lack of standardization, including naming conventions and
data output parameter scaling (e.g., NOX sensor output
scaling may vary between manufacturers), may lead to confusion and
inefficiencies when seeking replacement parts and performing
troubleshooting and repairs. SAE J2403 ``Medium-Heavy Duty E/E System
Diagnosis Nomenclature'' is designed to standardize nomenclature of
components and how systems with multiple sensors (e.g., multiple EGT
sensors) should be numbered starting from the same place (e.g.,
starting at the engine). CARB requires that, to the extent possible,
certification documentation shall use SAE J1930 or J2403 terms,
abbreviations, and acronyms. EPA is seeking comment on whether this
standard should be incorporated and required for use in naming certain
emission components such as exhaust temperature sensors as a part of
certification, maintenance instructions, diagnostic, or other
serviceability-related requirements.
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    \540\ Powerstrokehub.com, ``6.7L Power Stroke Emissions Control
System.'' Available here: http://www.powerstrokehub.com/6.7-power-stroke-emissions.html.
    \541\ Earlywine, Brad,''6.7L Power Stroke EGT Replacement.''
Available here: https://www.expertswrite.net/article/67l-powerstroke/changing-egt-sensors/.
---------------------------------------------------------------------------

    EPA seeks comment on other pertinent information that should be
included in owner's manuals so that owners can more easily understand
advanced emission control system operation and precautions that should
be taken in order to maintain them. To the extent EPA can ensure this
information is harmonized among manufacturers, we believe this could
improve owner, operators, parts counter specialist, and repair
technician experiences and reduce frustration which can lead to an
incentive to tamper.
iii. Request for Comments on Maintenance and Operational Information
for Improved Serviceability of Electric Vehicles
    EPA is requesting comment on several potential serviceability
requirements for BEV and FCEV technologies. Many of these potential
serviceability provisions are similar to those proposed in Section
IV.B.3.ii for CI and SI engines but are specific to these technologies
that do not require a combustion engine or emissions aftertreatment
system. As noted in the introduction of Section III.A, under 40 CFR
86.016-1(d)(4), heavy-duty BEV and FCEV manufacturers currently use
good engineering judgment to apply the criteria pollutant requirements
of part 86, Subpart S, including maintenance provisions.
    We are requesting comment on seven categories of potential
requirements for BEV and FCEV serviceability: (1) Labeling, (2)
purchaser guidance, (3) maintenance information, (4) maintenance
information requirements concerning the use of a standardized connector
and making malfunction codes and powertrain parameters accessible, (5)
onboard vehicle signals for service and repair technicians, (6)
information on battery energy used per trip, and (7) battery
information to facilitate battery recycling. We request comment on
whether each of these categories individually or in combination should
be finalized to support owners and repair technicians in maintaining
and repairing BEV and FCEV technologies, or if alternative provisions
suggested by commenters would better support these technologies while
minimizing burden to manufacturers. Each of these categories of
potential requirements is based on provisions of the 2019 CARB Zero
Emissions Powertrain Certification (ZEP Certification), which imposes
requirements on manufacturers choosing to generate NOX
emission credits under the CARB Omnibus rule.\542\ We believe that
adopting an approach based on the CARB ZEP Certification program would
provide manufacturers with consistency across the country. Consistent
with the ZEP Certification requirements, EPA believes that the
maintenance and operational information described in this section could
help potential BEV and FCEV purchasers to understand the possible
operational impacts of these technologies on their businesses, as well
as ensure the vehicles are supported during their use in the field.
Each of the areas in which we are requesting comment is briefly
discussed immediately below.
---------------------------------------------------------------------------

    \542\ CARB (2019) ``Final Statement of Reasons for Rulemaking,
Proposed Alternative Certification Requirements and Test Procedures
for Heavy-Duty Electric and Fuel Cell Vehicles and Proposed
Standards and Test Procedures for Zero Emission Powertrains.''
https://ww2.arb.ca.gov/sites/default/files/barcu/regact/2019/zepcert/fsor.pdf (accessed August 5, 2021).
---------------------------------------------------------------------------

    For the first area (labeling), as specified in the current 40 CFR
1037.125, all vehicle manufacturers currently must affix a label to
each vehicle with information such as manufacturer name, vehicle
certification family, and build date; however, some of the information
is specific to vehicles propelled by an engine (e.g., 40 CFR
1037.125(c)(6) requires manufacturers to specify the emission control
system).

We request comment on whether there is additional information specific
to BEVs and FCEVs that would be useful to include on the vehicle label
for repair technicians, owners, and inspection and maintenance
professionals. We also request input from commenters on whether we
should require a QR code on BEV and FCEV labels, similar to the
proposed QR code requirement in 40 CFR 1036.135(c). Specifically, the
BEV or FCEV label could include a QR code to a website which would
direct repair technicians, owners, or inspection and maintenance
facilities to a website with information including: A digital copy of
the owner's manual, vehicle family information, and powertrain
identification. Commenters are encouraged to provide details on how any
suggestions for additional information would help vehicle owners with
the repair and maintenance of BEVs or FCEVs, as well as the potential
burden to manufacturers to include such information on the vehicle
label.
    For the second area (purchaser guidance), we request comment on
whether EPA should require BEV and FCEV manufacturers to provide
purchaser guidance information to potential owners on aspects of BEV or
FCEV ownership that may differ from owning a vehicle with a CI or SI
engine. Immediately below, we provide several examples of the types of
information that manufacturers could provide in purchaser guidance if
we were to finalize such a requirement in this rule or another future
rulemaking. For instance, purchaser guidance could include the range
the vehicle is capable of driving over a specified duty-cycle, top
speed, and maximum grade. As another example, manufacturers could
describe how vehicle load, ambient temperatures, and battery
degradation impact range, top speed, or maximum grade. Manufacturers
could also provide potential purchasers estimates of the time required
for maintenance and repairs of common malfunctions, as well as
potential vehicle transportation costs. Finally, manufacturers could
clearly describe any warranty coverage of the battery and other key
powertrain components that would be covered (see Section IV.B.1.iv.b
for our proposed warranty requirements).\543\ To minimize manufacturer
burden, EPA could provide an example statement in 40 CFR part 1037 that
manufacturers could choose to use if they attest that the statement is
accurate for their vehicle; the example statement could largely mirror
the statement that was proposed by CARB under the 2019 CARB ZEP
Certification and subsequently adopted into current CARB regulations
for GHG emissions from 2014 and later model vehicles.\544\ While an
example statement provided by EPA would minimize manufacturer burden,
it would also, by necessity, be more generic and not reflect parameters
specific to a given vehicle model (e.g., range). We encourage
commenters to provide input on the potential benefits of manufacturers
providing such purchaser guidance relative to the potential burden to
manufacturers to provide such guidance.
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    \543\ As noted in Section IV.B.1.iv.b, the existing 40 CFR
1037.120(e) requires all manufacturers to describe in their owner's
manuals the warranty provisions that apply to the vehicle;
manufacturers could also provide the same information in purchaser
guidance such that it could help inform potential owners prior to
their purchase (i.e., prior to having an owner's manual for the
vehicle). Per discussion in IV.B.1.iv.b, the proposed warranty
requirements differ for manufacturers choosing to generate
NOX emission credits from BEVs or FCEVs versus
manufacturers choosing not to generate NOX emission
credits from these vehicles.
    \544\ See Attachment B, ``California Greenhouse Gas Exhaust
Emission Standards and Test Procedures for 2014 and Subsequent Model
Heavy-Duty Vehicles``, 3.17 Sales Disclosures, https://ww2.arb.ca.gov/sites/default/files/classic/regact/2019/zepcert/froattb.pdf (accessed 8/5/2021).
---------------------------------------------------------------------------

    For the third area (maintenance information), we request comment on
whether EPA should require BEV and FCEV manufacturers to make
additional maintenance information available to owners and repair
technicians. Under the current 40 CFR 1037.125(f) manufacturers make
the service manual and any required service tools available to third-
party repair facilities at reasonable cost; however, we request comment
on any information specific to BEVs or FCEVs that would be important
for repair technicians in maintaining and repairing BEV and FCEV
technologies. In addition, we request comment on whether EPA should
require manufacturers to describe in their certification application
the monitoring and diagnostic strategies they use for the BEV or FCEV;
these strategies would also be included in their service manuals. In
addition to being similar to existing requirements for vehicles powered
by an engine, this potential provision would be consistent with the ZEP
Certification requirements.\545\
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    \545\ See Attachment C, ``Proposed, California Standards and
Test Procedures for New 2021 and Subsequent Model Heavy-Duty Zero-
Emissions Powertrains'' for details of CARB serviceability
provisions available here: https://ww2.arb.ca.gov/sites/default/files/barcu/regact/2019/zepcert/froattc.pdf.
---------------------------------------------------------------------------

    For the fourth area (standardized connector and accessible
malfunction codes and powertrain parameters), we request comment on
whether EPA should require that BEV and FCEV manufacturers use a
standardized connector that is compatible with automotive scan tools,
and further that all malfunction codes and key powertrain parameters
must be readable by a generic automotive scan tool. Commenters are
encouraged to provide information on whether the use of a standardized
connector would facilitate repair of BEVs and FCEVs, and the utility of
making all malfunction codes and key powertrain parameters readable by
a generic scan tool. We also request stakeholder input on the potential
burden to manufacturers to make the standardized connector, malfunction
codes, and key powertrain parameters accessible.
    For the fifth area (onboard vehicle signals), we request comment on
whether EPA should require manufacturers to make powertrain monitoring
or diagnostic signals publicly accessible to repair and service
technicians to facilitate BEV and FCEV maintenance or repair. In
Section IV.I we request comment on whether and how manufacturers who
choose to generate NOX emission credits could make
information on battery or fuel cell durability readily accessible; here
we request comment on other potential parameters that may be useful for
maintaining and repairing BEVs and FCEVs:

 Energy Storage System State of Charge (SOCE)
    [cir] Function: Indicate the remaining energy left in the
battery(ies). Would allow users to identify battery degradation or
failure that may require maintenance or repair of the battery or
powertrain systems.
 Energy Storage System State of Range (SOCR)
    [cir] Function: Indicate the remaining range of the battery(ies).
Would allow users to identify battery degradation or failure that may
require maintenance or repair of the battery or powertrain systems.
 Drive Motor System Efficiency
    [cir] Function: Compare the energy use of the drive motor from the
current state to the as manufactured state to see degradation over time
(e.g., 100 percent being as manufactured and decreasing as the
performance of the drive motor decreases), or failure. Would allow
first owner and secondhand buyers to identify degradation in the
electric motor.
 Battery Temperature
    [cir] Function: Identify battery temperature. Would inform repair
technicians about when battery

thermal management system may need repair (e.g., identify when battery
thermal management system degradation impacts range or charge rate).
 Percent Regenerative Braking
    [cir] Function: Measure the amount of regenerative braking relative
to total capacity for capturing energy from regenerative braking.
Information could provide insight on when potential maintenance or
repair is needed for systems related to regenerative braking, as well
as feedback to users on driving behavior that results in greater energy
capture from regenerative braking.
 Charging Rate
    [cir] Function: Check performance of the inverter/converter and
batteries. Would allow service repair technicians to identify when
inverter/converter, batteries or other components may need repair.
 Charging System Performance
    [cir] Function: Identify current charge rate at optimal battery
temperature relative to charge rate at the time of manufacture. Would
allow service technicians to identify degradation or failure in key
components of the charging system.

Commenters are encouraged to provide input on whether each of the
listed parameters would be useful, or if there are additional
parameters that would be informative. We request that commenters
provide any additional specifics of why each signal would be useful for
EPA to include in the final rule, or as part of other future
rulemakings. We also invite stakeholder input on whether EPA should
recommend a common language for BEV and FCEV communication protocols
(e.g., J1979-2). Note that we are not requesting comment on whether and
how manufacturers would utilize signals or a common communication
protocol to monitor or diagnose problems. Commenters are encouraged to
provide information on why additional onboard vehicle information would
be important for BEV and FCEV repairs, and how EPA suggesting a common
communication protocol would, or would not, be useful for the industry.
    For the sixth area (battery energy used per trip), we request
comment on whether manufacturers already utilize onboard vehicle
sensors that could provide estimates of energy consumption per trip,
and whether manufacturers could readily provide energy consumption per
trip information through a dashboard display. We further request
comment on whether battery energy used per trip would support users
understanding normal variance in battery performance due to factors
such as terrain, driving behavior, and temperature, versus battery
performance degradation that would necessitate maintenance or repair of
the powertrain. EPA will consider information provided by commenters to
evaluate the potential benefits of users understanding when a battery
may need repair relative to the potential burden to manufactures to
make such information available to users.
    For the seventh area, we request comment (battery information) on
the utility and feasibility of adding a battery information requirement
for BEVs and FCEVs. If we were to include a battery information
requirement in the final rule, then manufacturers would: (1) Briefly
describe in their owner's manual how to handle the battery after it is
no longer capable of providing sufficient energy or power to the
vehicle (e.g., identify alternative uses and safe disposal methods for
the battery), and (2) affix a label on the battery, and include in the
owner's manual, information necessary to recycle the battery (e.g.,
manufacturer, chemistry, voltage, hazard statement, QR code to a
website for additional details). We believe such battery information
would be important for users to appropriately re-purpose, recycle, or
otherwise dispose of the battery, and thereby minimize total
environmental impact of the BEV or FCEV. Commenters are encouraged to
provide information on whether such battery information would
facilitate users identifying alternative uses for the battery or
otherwise recycling the battery. We are also interested in information
on the feasibility of vehicle manufacturers having sufficient
information from battery suppliers to provide information on battery
handling at the end of its life in a vehicle. EPA will consider
information provided in comments and weigh the potential environmental
benefits of users having battery information with the potential burden
to manufacturers to provide such information.
iv. Other Emission Controls Education Options
    In addition to our proposals to provide more easily accessible
service information for users, we are seeking comment on whether
educational programs and voluntary incentives could lead to better
maintenance and real-world emission benefits. We received comments in
response to the ANPR supportive of improving such educational
opportunities to promote an understanding of how advanced emission
control technologies function and the importance of emissions controls
as they relate to the broader economy and the environment. Some
commenters were generally supportive of using educational programs and
incentives to improve maintenance practices. Commenters generally
agreed that there are actions EPA could take to reduce the
misinformation surrounding advanced emission control systems and that
any action that EPA could take to improve access to easily-
understandable maintenance information would be helpful.\546\ NADA
commented that they would ``welcome new emission control outreach and
incentives to combat misperceptions that can lead to emissions
tampering or mal-maintenance.'' \547\ The Motor and Equipment
Manufacturers Association (MEMA) commented that priority should be
given to improving education and training offered to service facilities
and technicians to reduce the misdiagnoses of faulty emission
components where ``it is a common diagnostic technique in service
repair shops to continually swap out emissions components until the
problem goes away.'' \548\ Lubrizol suggested that EPA provide
education to ensure fleets understand the proper lubricants required to
maintain engines.\549\
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    \546\ See the comments of the Oregon Department of Environmental
Quality, Docket ID EPA-HQ-OAR-2019-0055-0464; Georgia Department of
Natural Resources, Docket ID EPA-HQ-OAR-2019-0055-0267; and the
anonymous comments in Docket ID EPA-HQ-OAR-2019-0055-0306.
    \547\ See the comments of the National Automobile Dealers
Association, Docket ID EPA-HQ-OAR-2019-0055-0369.
    \548\ See the comments of the Motor & Equipment Manufacturers
Association, Docket ID EPA-HQ-OAR-2019-0055-0462.
    \549\ See the comments of Lubrizol, Docket ID EPA-HQ-OAR-2019-
0055-0454.
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    We seek comment on the potential benefits of educational and/or
voluntary, incentive-based programs such as EPA's SmartWay program and
how such a program could be designed and implemented.\550\
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    \550\ Learn about SmartWay. Available online at: https://www.epa.gov/smartway/learn-about-smartway. Accessed October 3, 2019.
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4. Rebuilding
    Clean Air Act section 203(a)(3) prohibits removing or rendering
inoperative a certified engine's emission controls which typically
includes being paired with properly functioning aftertreatment devices.
The regulation at 40 CFR 1068.120 describes how this tampering
prohibition applies for engine rebuilding and other types of engine
maintenance. The regulation generally

requires that rebuilders return a certified engine to its original
configuration and keep records to document that the rebuilder had a
reasonable technical basis for believing that the rebuilt engine's
emission control system performs at least as well as the original
design.
    Since the rebuilding provisions in 40 CFR 1068.120 broadly apply to
everyone involved in restoring a rebuilt engine to its certified
configuration, to the extent that vehicle owners or others remove an
engine from and install a rebuilt engine in a heavy-duty highway
vehicle, we consider those steps to be part of the rebuilding process.
    We are not proposing new or modified rebuilding provisions in this
rule. However, we intend to continue to monitor rebuilding practices
and may develop updated regulatory provisions in a future rulemaking.
5. Maintenance
    Consistent with the CAA and existing regulations, our proposed
standards would apply over the applicable useful life. Manufacturers
perform testing to demonstrate that engines will meet emission
standards over the full useful life. Manufacturers may perform
scheduled maintenance on their test engines only as specified in the
owner's manual. As part of the certification process, manufacturers
must get EPA approval for such scheduled maintenance, which is also
subject to minimum maintenance intervals as described in the
regulations. In this section, we describe the updated maintenance
provisions we are proposing for heavy-duty highway engines. Section
IV.F of this preamble summarizes the current the durability
demonstration requirements and our proposed updates.
    Our proposed maintenance provisions, in a new section 40 CFR
1036.125, combine and amend the existing criteria pollutant maintenance
provisions from 40 CFR 86.004-25 and 86.010-38. Similar to other part
1036 sections we are adding in this proposal, the structure of the new
40 CFR 1036.125 is consistent with the maintenance sections in the
standard-setting parts of other sectors (e.g., nonroad compression-
ignition engines in 40 CFR 1039.125).\551\ In 40 CFR 1036.205(i), we
are proposing to codify the current manufacturer practice of including
maintenance instructions in their application for certification such
that approval of those instructions would be part of a manufacturer's
certification process.\552\ We are also proposing a new paragraph 40
CFR 1036.125(h) outlining several owner's manual requirements,
including migrated and updated provisions from 40 CFR 86.010-38(a). For
example, proposed 40 CFR 1036.125(h)(2) expands on the current
requirement for manufacturers to describe the documentation owners need
to provide to show maintenance occurred, by specifying that maintenance
instructions must clearly state how to ``properly maintain and use''
the engine. The new paragraph (h)(2) provides a clearer connection to
the regulatory requirements for warranty and defect reporting.
---------------------------------------------------------------------------

    \551\ Stout, Alan; Brakora, Jessica. Memorandum to docket EPA-
HQ-OAR-2019-0055. ``Technical Issues Related to Migrating Heavy-Duty
Highway Engine Certification Requirements from 40 CFR part 86,
subpart A, to 40 CFR part 1036``. October 1, 2021.
    \552\ See the current submission of maintenance instructions
provisions in 40 CFR 86.079-39.
---------------------------------------------------------------------------

    This section summarizes maintenance updates recently adopted by
CARB and introduces our proposed provisions to clarify the types of
maintenance, update the options for demonstrating critical emission-
related maintenance will occur and the minimum scheduled maintenance
intervals for certain components, and outline specific requirements for
maintenance instructions.
i. Recent Updates to CARB Maintenance Regulations
    In two recent rulemakings, CARB updated their maintenance
regulations and we considered CARB's approach when designing our
maintenance provisions for this proposal. In its Step 1 warranty
program, CARB lengthened the minimum allowable maintenance intervals
for heavy-duty diesel engines to reflect current industry norms for
scheduling replacement of emissions-related parts.\553\ CARB stated
that this change limits manufacturers' ability to transfer the
liability for part replacements to vehicle owners for emissions-related
parts during the lengthened warranty periods, further strengthening
warranty coverage.
---------------------------------------------------------------------------

    \553\ California Air Resources Board. HD Warranty 2018 Staff
Report: Initial Statement of Reasons. May 8, 2018. p III-9.
Available online: https://ww2.arb.ca.gov/rulemaking/2018/hd-warranty-2018.
---------------------------------------------------------------------------

    CARB staff surveyed owner's manuals for all 2016 California-
certified on-road heavy-duty diesel engines and compiled the intervals
manufacturers published for specific emission-related components. The
maintenance intervals published in the owner's manuals were at or above
the minimum intervals that currently apply for emission-related
components. For MY 2022 and later HD diesel engines, CARB updated their
minimum scheduled maintenance intervals to match the shortest (i.e.,
most frequent) interval from those published values for each component.
If no manufacturer published an interval for a given component, CARB
set the minimum maintenance interval for that component to match the
current useful life mileage (i.e., 435,000 miles for HHDD engines).
CARB's Step 1 program also provides that manufacturers cannot schedule
replacements for turbochargers, DPF elements, catalyst beds, or exhaust
gas recirculation systems during the useful life of the engine unless
the manufacturer agrees to pay for the replacements. These four
emission-related components were chosen due to their direct emissions
impact or high cost to replace. Furthermore, CARB clarified that there
shall be no scheduled maintenance interval throughout the applicable
useful life for sensors or actuators that are integrated with the
turbocharger or exhaust gas recirculation (EGR) valve/cooler
components, as these parts cannot easily be replaced without removing
the larger systems from the engine. Other sensors and actuators that
are necessary for the proper function of other emissions-critical
systems or are not integrated with the turbocharger or EGR systems can
be included on a maintenance schedule at a minimum interval of 150,000
miles.
    CARB's HD Omnibus rulemaking did not include further updates to the
maintenance provisions for diesel engines but addressed HD Otto-cycle
engines and hybrid vehicles.\554\ Similar to their strategy to identify
maintenance intervals for diesel engines, CARB surveyed owner's manuals
for 2018 California-certified HD Otto-cycle engines and updated the
minimum maintenance intervals for MY 2024 and later HD Otto-cycle
engines based on the shortest intervals published. For gasoline
vehicles, EGR systems and catalyst beds were designated ``not
replaceable'' components. CARB further clarified that the same minimum
intervals apply to diesel- and Otto-cycle engines used in hybrid
vehicles.
---------------------------------------------------------------------------

    \554\ California Air Resources Board. Staff Report: Initial
Statement of Reasons-Public Hearing to Consider the Proposed Heavy-
Duty Engine and Vehicle Omnibus Regulation and Associated
Amendments. June 23, 2020. Page III--49.
---------------------------------------------------------------------------

ii. Types of Maintenance
    Our proposed new 40 CFR 1036.125 clarifies that maintenance
includes any inspection, adjustment, cleaning, repair, or replacement
of components and, consistent with 40 CFR 86.004-25(a)(2), broadly
classifies maintenance as

emission-related or non-emission-related and scheduled or unscheduled.
We propose to define the following five types of maintenance that
manufacturers may choose to schedule:

 Critical emission-related maintenance
 Recommended additional maintenance
 Special maintenance
 Noncritical emission-related maintenance
 Non-emission-related maintenance

    We are proposing to define these maintenance categories to
distinguish between the types of maintenance manufacturers may choose
to recommend to owners in maintenance instructions, identify the
requirements that apply to maintenance performed during certification
durability demonstrations, and clarify the relationship between the
different types of maintenance, emissions warranty requirements, and
in-use testing requirements. The proposed provisions described in this
section specify the conditions for scheduling each of these five
maintenance categories. Unscheduled maintenance (i.e., repair of failed
components) is unpredictable and would not be included in a
manufacturer's maintenance instructions or durability
demonstration.\555\
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    \555\ The current provisions of 40 CFR part 1068 describe a
manufacturer's requirements relating to failed emission-related
components with respect to emission-related warranty (40 CFR
1068.110(e)) and defect and recall (1068, subpart F). We are
proposing to note in a new paragraph 40 CFR 1036.125(h)(2) that
manufacturers may identify failure to repair critical emission-
related components as improper maintenance if the repairs are
related to an observed defect.
---------------------------------------------------------------------------

    A primary focus of the current and proposed maintenance provisions
is critical emission-related maintenance. Critical emission-related
maintenance includes any adjustment, cleaning, repair, or replacement
of emission-related components that manufacturers identify as having a
critical role in the emission control of their engines.\556\ Consistent
with the current 40 CFR 86.004-25(b)(6)(ii), our proposed 40 CFR
1036.125(a)(1) allows manufacturers to schedule critical emission-
related maintenance in their maintenance instructions based on the
manufacturer meeting two conditions: The manufacturer demonstrates the
maintenance is reasonably likely to occur on in-use engines, and the
recommended intervals are at least as long as the minimum intervals set
by EPA. We describe our proposed conditions for demonstrating critical
emission-related maintenance will occur in Section IV.B.5.iii. In
Section IV.B.5.iv, we describe our proposal to update the minimum
maintenance intervals currently specified in 40 CFR 86.004-25(b)(3) and
(4) for certain critical emission-related components. For new
technology, not included in the list of proposed components with
specified minimum maintenance intervals, we are proposing to migrate
and update the process specified in 40 CFR 86.094-25(b)(7), as
described in Section IV.B.5.v.
---------------------------------------------------------------------------

    \556\ See Section IV.B.5.iv for our proposed definition of
critical emission-related components and a list of common critical
emission-related components for which we are proposing to specify
minimum scheduled maintenance intervals.
---------------------------------------------------------------------------

    The four other types of maintenance would require varying levels of
EPA approval. In 40 CFR 1036.125(b), we propose to define recommended
additional maintenance as maintenance that manufacturers recommend
owners perform for critical emission-related components in addition to
what is approved for those components under 40 CFR 1036.125(a). A
manufacturer may recommend that owners replace a critical emission-
related component at a shorter interval than the manufacturer received
approval to schedule for critical emission-related maintenance;
however, the manufacturer would have to clearly distinguish their
recommended intervals from the critical emission-related scheduled
maintenance in their maintenance instructions. As described below,
recommended additional maintenance is not performed in the durability
demonstration and cannot be used to deny a warranty claim, so
manufacturers would not be limited by the minimum maintenance intervals
or need the same approval from EPA by demonstrating the maintenance
would occur. Special maintenance, proposed in 40 CFR 1036.125(c), would
be more frequent maintenance approved at shorter intervals to address
special situations, such as atypical engine operation. Manufacturers
would clearly state that the maintenance is associated with a special
situation in the maintenance instructions provided to EPA and owners.
Our proposed definition of noncritical emission-related maintenance,
which is based on 40 CFR 86.010-38(d), includes inspections and
maintenance that is performed on emission-related components but is
considered ``noncritical'' because emission control will be unaffected.
As specified in proposed 40 CFR 1036.125(d), manufacturers may
recommend noncritical emission-related inspections and maintenance in
their maintenance instructions if they clearly state that it is not
required to maintain the emissions warranty. Finally, we define ``non-
emission-related maintenance'' as maintenance unrelated to emission
controls (e.g., oil changes) in proposed 40 CFR 1036.125(e). We propose
that manufacturers' maintenance instructions can include any amount of
nonemission-related maintenance that is needed for proper functioning
of the engine.
    Maintenance instructions play an important role in the service
accumulation portion of a manufacturer's durability demonstration. We
currently require that all emission-related scheduled maintenance
during durability testing occur on the same schedule as specified in
the maintenance instructions for the purchaser.\557\ When accumulating
equivalent miles on an engine, manufacturers are currently allowed to
perform maintenance according to their maintenance instructions. In
this proposal, we clarify how this relates to the specific types of
maintenance in proposed 40 CFR 1036.125. Consistent with current
maintenance provisions, we propose that manufacturers can perform
critical emission-related maintenance at their approved schedules
during a durability demonstration. Since the proposed recommended
additional maintenance provisions do not include the same requirement
to demonstrate the maintenance will occur in-use, manufacturers could
not perform recommended additional maintenance during their durability
demonstration. Special maintenance would also not be performed during a
durability demonstration, since laboratory-based testing does not
reflect atypical operation. We propose that manufacturers may perform
noncritical emission-related inspections on their engines during their
durability demonstration at any frequency, but could only adjust,
clean, repair, or replace a component in response to an inspection if
scheduled maintenance is approved for that component. We propose
manufacturers can perform any amount of nonemission-related maintenance
that is needed for proper functioning of the engine during durability
testing.
---------------------------------------------------------------------------

    \557\ See 40 CFR 86.094-25(b).
---------------------------------------------------------------------------

    The current general warranty requirements of 40 CFR 1068.115(a)
allow a manufacturer to deny warranty claims for failures resulting
from improper maintenance or use. We are proposing a new owner's manual
requirement for manufacturers to specifically identify the steps an
owner

must take to properly maintain the engine, including documentation a
manufacturer may require for an owner to demonstrate the maintenance
occurred. In 40 CFR 1036.125, we propose to clarify the relationship
between the different types of maintenance and emissions warranty
requirements, and specify when manufacturers must note in their
maintenance instructions (i.e., owner's manual) if a maintenance type
cannot be used as the basis to deny a warranty claim. We expect
manufacturers would only schedule critical emission-related maintenance
and make the effort to demonstrate the maintenance is likely to occur
in-use for components that they recognize are strongly connected to
emission performance. As a result, our current maintenance provisions
allow, and our proposed provisions would continue to allow,
manufacturers to deny warranty claims if owners do not perform critical
emission-related maintenance at the recommended schedule, as specified
in 40 CFR 1068.115. Failure to perform recommended additional
maintenance could potentially impact emissions, but manufacturers would
not be able to deny a warranty claim if owners do not perform it,
because manufacturers would not have taken the extra steps to have it
approved as critical Manufacturers would be able to deny warranty
claims if an owner did not perform the special maintenance after it was
determined that the engine was operated in conditions that meet the
special situation described in the maintenance instructions. In
contrast, manufacturers would not be able to deny a warranty claim
citing ``improper maintenance or use'' for atypical operation if an
owner follows the corresponding special maintenance instructions. We
propose that failure to perform noncritical emission-related
maintenance and nonemission-related maintenance cannot be used to deny
emissions warranties.
    Since failure to perform maintenance may also impact emissions when
the engine is in use, we have also identified the relationship between
the maintenance types and in-use testing. Compression-ignition engine
manufacturers are subject to off-cycle standards for in-use engines. As
part of the proposed manufacturer-run testing program in subpart E, we
specify that manufacturers can select vehicles and engines for testing
based on proper maintenance and use (see 40 CFR 1036.410(b)(2)). In 40
CFR 1036.125, we propose that if recommended additional maintenance or
noncritical emission-related maintenance is not performed on an engine,
it does not disqualify the engine from in-use testing. Manufacturers
may reject an engine for in-use testing if the other types of
maintenance (i.e., critical emission-related maintenance, special
maintenance, or nonemission-related maintenance) were not performed,
consistent with current provisions in 40 CFR 86.1908.
iii. Critical Emission-related Maintenance Demonstration
    One of the current conditions for allowing scheduled maintenance to
be performed during the durability demonstration is that manufacturers
demonstrate the maintenance is reasonably likely to be performed in-
use.\558\ For critical emission-related scheduled maintenance, we are
generally including these same requirements in our proposed new
paragraph 40 CFR 1036.125(a)(1), with clarifications noted below.
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    \558\ See 40 CFR 86.004-25 and 86.094-25.
---------------------------------------------------------------------------

    Under proposed 40 CFR 1036.125(a)(1)(i), manufacturers could
demonstrate that the critical maintenance is reasonably likely to occur
in-use on the recommended schedule by providing data showing that the
engine's performance unacceptably degrades if the maintenance is not
performed, consistent with 40 CFR 86.004-25(a)(6)(ii)(A). In this
proposal, we clarify that this paragraph is intended to cover emission
control technologies that have an inherent performance degradation that
coincides with emission increases, such as back pressure resulting from
a clogged DPF, and is not intended to apply to inducements where a
manufacturer-specified performance derate is triggered in response to a
detected or predicted emission increase. We are proposing a separate
statement in 40 CFR 1036.125(a)(1) that points to the new proposed
inducement provisions noting that we would accept DEF replenishment as
reasonably likely to occur if an engine meets the specifications in
proposed 40 CFR 1036.111.
    Under proposed 40 CFR 1036.125 (a)(1)(ii) and consistent with 40
CFR 86.004-25(a)(6)(ii)(C), manufacturers could demonstrate a
reasonable likelihood that the critical maintenance will be performed
in-use by including a system that displays a visible signal to alert
drivers that maintenance is due. We are proposing additional criteria
for use of this visible signal, including that it be continuously
displayed while the engine is operating and not easily eliminated
without performing the specified maintenance. We request comment on
this proposal and any additional criteria we should consider before
approving a visible signal as a method to ensure critical emission-
related scheduled maintenance is performed.
    Under proposed 40 CFR 1036.125(a)(1)(iii), manufacturers could
present survey data showing that 80 percent of engines in the field
receive the specified maintenance. We are maintaining this existing
option (see paragraphs (B) and (D) of 40 CFR 86.004-25(a)(6)(ii)) in
our proposal but note that manufacturers have not presented survey data
related to scheduled maintenance in recent years. We request comment on
this option and any updates we should consider, including how telematic
data could be applied and if 80 percent continues to be an appropriate
threshold.
    We are also proposing in 40 CFR 1036.125(a)(1)(iv) to continue an
existing provision in 40 CFR 86.004-25(a)(6)(ii)(E) that a manufacturer
may rely on a clear statement in their maintenance instructions for
owners that it will provide the critical maintenance free of charge.
Finally, we propose to continue to allow manufacturers to present other
options for approval by EPA to demonstrate that critical emission-
related maintenance is reasonably likely to occur (see proposed 40 CFR
1036.125(a)(1)(v) and current 40 CFR 86.004-25(a)(6)(ii)(F)).
iv. Emission-Related Components and Minimum Maintenance Intervals
    Manufacturers, with EPA approval, may define scheduled maintenance
for emission-related components, which would be included in maintenance
instructions directing owners to adjust, clean, or replace components
at specified intervals. The current regulations in 40 CFR 86.004-25(b)
specify minimum maintenance intervals for emission-related components,
such that manufacturers may not specify more frequent maintenance than
we allow. We propose to migrate and update the minimum maintenance
intervals from part 86, subpart A to 40 CFR 1036.125(a). These proposed
minimum intervals would apply for the scheduled adjustment, cleaning,
or replacement of many common critical emission-related components, as
described in this section. We are proposing not to migrate the list of
critical emission-related components currently specified in 40 CFR
86.004-25, and instead are proposing a new definition of ``critical
emission-related

component'' in 40 CFR 1068.30 that refers to 40 CFR part 1068, appendix
A.
    As part of the migration to part 1036, we are proposing to update
the lists of components with minimum maintenance intervals to more
accurately reflect components in use today. We are not including
carburetors, idle mixture, and particulate trap oxidizers in the
proposed 40 CFR 1036.125 as these components are obsolete. Our proposed
language replaces the part 86 diesel particulate trap intervals with a
more general ``particulate filtration system'' that can apply to
particulate filters intended for SI or CI engines. We also no longer
specify an interval for electronic engine control units as we are
unaware of any scheduled maintenance for those components. Our proposed
minimum maintenance intervals for each emission-related component or
system continue to apply to any associated sensors or actuators. We are
further proposing that these intervals also apply to any hoses, valves,
and wiring connected to the component or system, such that
manufacturers would ensure that all parts necessary to keep the
component functional, including wires and wiring harnesses, remain
durable throughout useful life or schedule appropriate maintenance to
address any durability concerns.
    We propose not to migrate the 100,000-mile minimum interval for
Spark-ignition HDE evaporative emission canister to 40 CFR 1036.125,
since evaporative emission control systems are covered under the
vehicle provisions of part 1037. Similarly, we propose that components
in the refueling emission control system that would be used to meet the
proposed refueling standards for certain SI HDE, including the carbon
canisters, filler pipes and seals, refueling flow controls, purge
systems, and related wiring, actuators, and sensors, would also be
covered under the maintenance provisions of part 1037.
    We are proposing to add minimum scheduled replacement intervals for
other components and systems that correspond to technologies we expect
to be considered by manufacturers for meeting our proposed standards.
In general, the proposed minimum replacement intervals are set at the
current useful life for each engine class, since we do not have data
indicating that manufacturers are scheduling maintenance for these
components within the current useful life. We are proposing
NOX sensor minimum intervals at the current useful life
mileages for the Light, Medium, and Heavy HDE classes. We also propose
to add minimum intervals for replacing a rechargeable energy storage
system (RESS) in hybrid vehicles. Our proposed minimum intervals for
RESS equal the current useful life for the primary intended service
classes of the engines that these electric power systems are intended
to supplement or replace. We are not specifying distinct minimum
intervals for the electric power system components of BEVs and FCEVs;
instead, manufacturers could request approval for an interval using 40
CFR 1037.125(a).
    Considering our proposed lengthened useful life periods, we
reevaluated the current minimum maintenance intervals for replacing
components and are proposing to extend the replacement intervals such
that they reflect the scheduled maintenance of components today. Table
IV-11 summarizes the minimum replacement interval mileages we are
proposing in a new table in 40 CFR 1036.125(a). Similar to the minimum
maintenance interval approach adopted by CARB in their recent
rulemakings (see Section IV.B.5.i), we are proposing to base our
revised minimum replacement intervals on the scheduled maintenance
submitted by engine manufacturers for certifying recent model year
engines.\559\ We believe it is appropriate to account for replacement
intervals that manufacturers have already identified and demonstrated
will occur for these components and we are proposing replacement
intervals for these components that align with the shortest mileage
interval (i.e., most frequent maintenance) of the published values. We
propose to update the minimum replacement mileages for remaining
components that currently do not have specified maintenance intervals
in the current list from the current 100,000 or 150,000 miles to the
current useful life mileage for each primary intended service class.
Since manufacturers are not scheduling replacement of these other
components within the current useful life of their engines today, we do
not expect manufacturers would have a technical need to do so in the
future. We are not proposing to update the maintenance intervals for
adjusting or cleaning critical emission-related components. These
intervals are proposed to be migrated, with updated component names
consistent with the proposed replacement intervals, from 40 CFR 86.004-
25 into a proposed new table in 40 CFR 1036.125(a). Consistent with
current regulations, our proposed 40 CFR 1036.125(a) would continue to
allow manufacturers to seek advance approval for new emission-related
maintenance they wish to include in maintenance instructions and
perform during durability demonstration.
---------------------------------------------------------------------------

    \559\ Brakora, Jessica. Memorandum to docket EPA-HQ-OAR-2019-
055. ``Approved Scheduled Maintenance Intervals for MY 2019
Certified Heavy-Duty Engines'', April 27, 2021.

Table IV-11--Proposed Minimum Scheduled Maintenance Intervals for Replacing Critical Emission-Related Components
                                                in 40 CR 1036.125
----------------------------------------------------------------------------------------------------------------
                                                       Accumulated miles (hours) for components
                                    ----------------------------------------------------------------------------
             Component                 Spark-ignition
                                            HDE             Light HDE          Medium HDE          Heavy HDE
----------------------------------------------------------------------------------------------------------------
Spark plugs........................       25,000 (750)                 NA                 NA                  NA
DEF filters........................                 NA    100,000 (3,000)    120,000 (3,600)     175,000 (5,250)
Crankcase ventilation valves and        60,000 (1,800)     60,000 (1,800)     60,000 (1,800)      60,000 (1,800)
 filters...........................
Oxygen sensors.....................     80,000 (2,400)                 NA                 NA                  NA
Ignition wires.....................    100,000 (3,000)                 NA                 NA                  NA
Air injection system components....    110,000 (3,300)                 NA                 NA                  NA
Particulate filtration system          100,000 (3,000)    100,000 (3,000)    250,000 (7,500)     250,000 (7,500)
 (other than filter elements)......
Catalyst systems (other than           110,000 (3,300)    110,000 (3,300)    185,000 (5,550)    435,000 (13,050)
 catalyst beds); Fuel injectors;
 Electronic control modules;
 Evaporative emission canisters;
 Turbochargers; EGR system
 components (including filters and
 coolers)..........................
----------------------------------------------------------------------------------------------------------------

   Table IV-12--Proposed Minimum Scheduled Maintenance Intervals for Adjusting and Cleaning Critical Emission-
                                      Related Components in 40 CR 1036.125
----------------------------------------------------------------------------------------------------------------
                                                       Accumulated miles (hours) for components
                                     ---------------------------------------------------------------------------
     Components and systems \a\         Spark-ignition
                                             HDE             Light HDE          Medium HDE         Heavy HDE
----------------------------------------------------------------------------------------------------------------
Spark plugs.........................       25,000 (750)                 NA                 NA                 NA
EGR-related filters and coolers;         50,000 (1,500)     50,000 (1,500)     50,000 (1,500)     50,000 (1,500)
 Fuel injectors; Crankcase
 ventilation valves and filters.....
DEF filters.........................                 NA     50,000 (1,500)     50,000 (1,500)     50,000 (1,500)
Ignition wire; Idle mixture.........     50,000 (1,500)                 NA                 NA                 NA
Oxygen sensors......................     80,000 (2,400)                 NA                 NA                 NA
Air injection system components.....    100,000 (3,000)                 NA                 NA                 NA
Catalyst system components; EGR         100,000 (3,000)    100,000 (3,000)    150,000 (4,500)    150,000 (4,500)
 system components (other than
 filters or coolers); Particulate
 filtration system components;
 Turbochargers......................
----------------------------------------------------------------------------------------------------------------

    The minimum maintenance intervals presented in Table IV-11 and
Table IV-12 are based on mileage, since equivalent mileage accumulation
is the parameter used for the durability demonstration. Consistent with
our current maintenance provisions, we are proposing corresponding
minimum hours values based on a 33 miles per hour vehicle speed (e.g.,
150,000 miles would equate to 4,500 hours). We request comment on the
conversion factor between mileage and hours, noting that hours would
not apply to the manufacturers' durability demonstrations, but may
impact the frequency of scheduled maintenance for owners with lower
speed vehicle applications.\560\ Consistent with the current
maintenance intervals specified in part 86, we are not proposing year-
based minimum intervals; OEMs can use good engineering judgment if they
choose to include a scheduled maintenance interval based on years in
their owner's manuals, which is expected to only be used by a small
number of infrequently operated vehicles. We request comment on the
need to specify a minimum year-based interval, including data on
average annual mileages to convert the minimum mileage intervals to
years for each of the primary intended service classes.
---------------------------------------------------------------------------

    \560\ We are proposing a 20 miles per hour average vehicle speed
to distinguish low speed vehicles in our emissions warranty proposal
(see Section IV.B.1) and in our inducement proposal (see Section
IV.D).
---------------------------------------------------------------------------

    We request comment on all components and systems presented in Table
IV-11 and Table IV-12 and the corresponding minimum scheduled
maintenance intervals. Specifically, we request data to support
different interval values or specific components that should have
intervals distinct from presented systems. We request comment on our
proposal to update the list of components and systems, whether
additional components should be considered, and if any of the listed
components or systems should be more clearly defined. Additionally, if
a commenter believes there is value in prioritizing or otherwise
grouping emission control components, we encourage them to suggest
criteria to classify the components. We request comment on the numeric
values of the replacement intervals proposed, and our proposal to
preserve the current minimum intervals for adjusting and cleaning
components. Manufacturers and suppliers have shown an interest in
developing modular emission controls that can be serviced more easily.
We request comment on the specific emission control systems that may
use modular components, criteria for defining ``modular'', and
adjustments to the proposed minimum maintenance intervals or
replacement restrictions we should consider to account for improved
serviceability of modular components.
v. Critical Emission-Related Maintenance for New Technology
    Current provisions of 40 CFR 86.094-25(b)(7) outline a process for
manufacturers to seek approval for new scheduled maintenance that
includes an EPA announcement of the maintenance interval in the Federal
Register. Regarding new scheduled maintenance on existing technology,
we are proposing not to migrate the provision in 40 CFR 86.094-
25(b)(7)(i) for maintenance practices that existed before 1980.
Instead, the maintenance demonstration and minimum maintenance interval
provisions we are proposing in the new 40 CFR 1036.125(a) would cover
the current process for new maintenance on critical emission-related
components currently in use.
    Regarding scheduled maintenance on new technology, the provision
currently in 40 CFR 86.094-25(b)(7)(ii) provides a process for approval
of new critical emission-related maintenance associated with new
technology. We recognize that new emission control technology may be
developed in the future and it is important to retain a public process
for approving maintenance associated with new technology. We are
proposing to migrate and update 40 CFR 86.094-25(b)(7)(ii) into a new
40 CFR 1036.125(a)(3) for scheduled critical emission-related
maintenance associated with new technology. We are proposing to use
model year 2020 as the reference point for considering whether
technology is new. Manufacturers using new technology would request a
recommended maintenance interval, including data to support the need
for the maintenance, and demonstrate that the maintenance is likely to
occur at the recommended interval using one of the conditions proposed
in 40 CFR 1036.125(a)(1). We are also proposing to continue our
responsibility to communicate such a decision on maintenance for new
technology. As such, we propose to retain EPA's obligation to publish a
Federal Register notice based on information manufacturers submit and
any other available information to announce that we have established
new allowable minimum maintenance intervals.
    Manufacturers would also continue to have the option currently
specified in 40 CFR 86.094-25(b)(7)(iii) to ask for a hearing if they
object to our decision. Hearing procedures are specified in 40 CFR
1036.820 and 40 CFR part 1068, subpart G, including proposed new
provisions in 40 CFR part 1068. We request comment on our proposed
maintenance provisions for new technology, including our proposal to

use model year 2020 to distinguish ``new'' technology.
vi. Payment for Scheduled Maintenance
    The minimum maintenance intervals specified in Table IV-11 would
apply for replacement of the listed components and systems. While we
are proposing replacement intervals for other components in the
catalyst and particulate filtration systems, current maintenance
provisions in 40 CFR 86.004-25(b)(4)(iii) state that only adjustment
and cleaning are allowed for catalyst beds and particulate filter
elements and that replacement is not allowed during the useful life.
Current 40 CFR 86.004 25(i) clarifies that these components could be
replaced or repaired if manufacturers demonstrate the maintenance will
occur and the manufacturer pays for it. We propose to continue to
restrict replacement of catalyst beds and particulate filter elements,
requiring that manufacturers pay for the repair or replacement of
catalyst beds and particulate filter elements, if needed, within the
regulatory useful life.
    We are proposing to identify these and other components with
limited replacement using four criteria based on current provisions
that apply for nonroad compression-ignition engines.\561\ Our proposed
40 CFR 1036.125(g) states that manufacturers would pay for scheduled
maintenance, including parts and labor, if all the following criteria
are met:
---------------------------------------------------------------------------

    \561\ See 40 CFR 1039.125(g).
---------------------------------------------------------------------------

     Each affected component was not in general use on similar
engines before 1980,
     The primary function of each affected component is to
reduce emissions,
     The cost of the scheduled maintenance is more than 2
percent of the price of the engine, and
     Failure to perform the maintenance would not significantly
degrade the engine's performance.
    Scheduled maintenance for the replacement of catalyst beds and