Service Trailer Brake System Problem

carnau · August 4, 2018

Fixed a C1117 tonight for the Service trailer brake system light on the 2014 - 2018 trucks and uploaded a repair video to youtube. I know this is an old post just adding it to this thread just in case anyone else has this same issue can search and find the repair video. Thanks!

carnau · July 5, 2019

I made a Video for the trailer brake on Tahoe's, Yukon's and Suburbans since it requires a little different replacement.

wmbryant57 · August 4, 2019

Probably reviving an old topic. Just bought a 2016 Tahoe LTZ one month ago. After 4 days had to replace the battery. Now yesterday when in the middle of a 70+ mile drive, started getting the "Service Trailer Brake System" and "Service Stabilitrak" messages. Just a couple times, then it happened 4-5 times on the way home. Would only come up with braking or signaling with cruise control active. Now this morning I go to start the car and nothing. It unlocked fine. Pushed the start button and everything went blank. Like the battery was disconnected. Got out, shut the door, opened the door and tried again, and everything was fine. Going to call the dealer tomorrow, but it sounds like a grounding issue to me. Anybody have any thoughts?

Matt Larkins · August 12, 2019

I have a 2018 gmc sierra all terrain. The steering assist light came on when I started it, so the steering was rock hard, service trailer brake light on, a/c didn't work for a little hit AND truck was in limp mode, tras mission wouldn't shift. At first it wouldn't even go into gear. After i cycled the key on and off a few times I at least I got the electric steering back. This is the second time this truck has done this! The first time it had 964 miles on the truck! And of course when I limped it back to the dealer everything was working! All the codes were for all the modules not communicating with each other. Now it has 5050 miles on it and it's doing it again! I just had it a couple of days ago for the service 4WD light came on. They said they updated transfercase module software. I really hope I didn't buy a lemon! Has anyone have a similar situation?