Feb 13, 2021 · This code U0100 popped up last week when I started the truck, but it drove fine. I do have an unlocked pcm with a Hemifever tune. Couple weeks ago i installed a new tune for …

Dec 28, 2010 · Re: Check Engine Code U0100 Hello Restomod, Welcome to the forum! I am sorry to hear of the vehicle issue you've encountered. If you would like my assistance …

Jun 21, 2024 · Hi Everyone, I have been chasing my tail for some time now and am hoping someone could shed some light on my issue. I have been searching through the forum with no …

Oct 5, 2016 · Car is Dead - Cannot Connect to ECM - U0100 - help? Jump to Latest 40K views 27 replies 10 participants last post by payne Feb 14, 2018 P

Dec 9, 2025 · 2007 Escalade Having Communication Issues Vehicle Still Runs And Drives ! locks going on and off Gauges going crazy Slow acceleration Hesitant shifting ABS Light CEL Light …

Aug 8, 2022 · Fixing PCM communication error - no-crank & radio giving anti-theft code error

Feb 2, 2019 · The truck never went into eco mode so I took it back home. I read the code and it was U0100. Letting the truck off for 3 hours the code is still there. Any of you had this issue? …

Jul 28, 2015 · Hi fellow owners, I have a 2009 CTS with DI V6. My wife and I went to go shoping. The car stated fine. Then gave a few chugs and shut down. The engine will not start or even …

May 8, 2023 · The only code I got was U0100 which means no communication with ECM. Battery was fully charged during all of this and had the same results over many attempts. Eventually I …

Oct 12, 2015 · U0100 - TCM Lost Comm with ECM this and every ignition cycle. This is the first time I've had to hook the Tech II up to the V and I found out my software isn't up to date for the …