How to Fix Vacuum Door Lock Failure in Mercedes

Mercedes Door Panel

The Mercedes Benz is a luxury vehicle that many dream of owning. They are known as beautiful, reliable vehicles, so once you invest in one it is important to keep it operating in peak condition. Even when something relatively minor goes wrong, you’ll want it taken care of quickly.

Regardless of the type of car you have, you want it to perform at the height of its abilities and help make your life more convenient. When you own a nicer, more luxurious car, you want that to perform at an even higher level, one that Mercedes is known for presenting. However, even well-made, beautiful cars–like a Mercedes–are prone to real-world problems. One of these is an issue with the vacuum door lock.

Potential Causes

A problem with the vacuum door lock can be dangerous–mostly to the belongings in your car, rather than your safety. The lack of functioning door lock means that the door will not lock, and others could access your car when it’s left unattended.

One of most common reasons that the vacuum door lock fails is because of a leaking actuator. The actuator is the part of your car that is responsible for operating the actual door locks.

Another common issue is that the vacuum pump fails, leading to a failure in the door lock itself. Essentially, this crucial component creates a vacuum that causes the lock mechanisms to move. When this fails, it prevents the door lock from working correctly. Also, the older a system is (so if you have an older car) the more likely that the locking system could fail, as wear and tear will take its toll and make failure more common. As your car ages, make sure you’re paying attention to whether or not your door locks are responding as they should.

How to Fix It

While it’s probably a better idea to just call a professional mechanic, you can also take a crack at fixing the issue yourself. It requires opening the hood, and disconnecting the three key lines that connect the vacuum. Blowing and sucking air out of the each of the key lines indicates whether the line is still good; if you can blow and suck, the line is shot and needs to be replaced. The next step requires a hand vacuum and replacement of the lines.

How Can You Tell?

Just because you’re aware that this problem could happen doesn’t mean that you know how to find it, or that you’ll know what to look for when it happens. The door locks are unlikely to stop working at once; rather, the doors will begin to fail systemically. Essentially, this means that the passenger door may stop working before the driver’s side. The fact that the one door stops working is a good indication that the door locks have started to be impacted by age or other damage, and it might be a good idea to take the car to a trusted repair shop before the rest of the doors become problematic.

Mercedes Vacuum Door Lock Issue Fix

Because actuators are expensive to replace, it’s a good idea to make sure that the vacuum door lock is the broken item. When in doubt, a mechanic or dealer should be able to answer this question. There are ways you can check yourself, but if you’re not sure you can do it properly, you should seek professional help.

What to Do

Seeking a trusted mechanic is always a safe bet, especially when you’re dealing with an expensive and luxurious car. That’s why Euro Plus Automotive is ready to deal with any and all of your car needs. We understand the safety and care that you want invested in your car, and we want to make sure that we treat it with the care that it deserves. Our specialist technicians are trained to work with all German and Japanese vehicles, including your prized Mercedes.

Mercedes Benz LogoWe have been offering dealership-quality care at affordable prices, and have been serving the San Fernando Valley for over 3 decades. Convenient to Canoga Park, Woodland Hills, San Fernando Valley, and Los Angeles County, CA, we’re prepared to take on any challenge that you send our way.

* Mercedes Benz Logo image credit goes to: SUNG YOON JO.


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