 From August 1985 to June 1992, Díaz Colón served with the 101st Troop Command at Headquarters, State Area Command, San Juan, Puerto Rico.On July 24, 1987, he was promoted to Lieutenant Colonel and during the years in which he served at Headquarters, he served in various positions including that of Executive Officer.On July 23, 1992, Díaz Colón was promoted to the rank of Colonel in the Regular Army and on December 22, of the same year he was promoted to the rank of Brigadier General.