Mine stopped working in the early spring. I had issues with flickering head lights that took months to fix. After that, took it in because I had a check engine light for my fuel management system, as soon as I parked at the dealership the light went away and they said they couldn't see any faults in the history. A few weeks later I started getting notifications at every power on that my collision detection system isn't working (still happening). Tried turning system off and on via the control panel, tried resetting my settings, made sure the front glass is spotless, nothing worked. While I wouldn't be too upset about this, as I'm a fairly defensive and safe driver, it also affects the adaptive cruise control. The 12 hour drive to Florida my family just made really revitalized my contempt for this issue. I haven't been back to the dealership yet as I was/am tired of taking a new truck back to the dealership every few weeks for some new issue, but I will be calling them tomorrow to start the process. When I was going through the headlight issue, I dealt with 2 different dealerships around 10 times, called GM's technical support several times to file claims, and finally submitted a claim to the National Highway Traffic Safety Administration (NHTSA). A few weeks later GM issued a recall. Took about 2 months. Point being, the process will likely take time and persistence.
Collision avoidance system does not work
- Thread starter ghost
- Start date
ghost
New member
No head light issue , never had a code. My Gap/following distance has never worked, and I rarely see ECO indicating Active Fuel Mgmt activation. Again dealer response has been no codes therefore no problem. I also filed with NHTSA. Do you have a contact with GM technical support, their Customer Service is useless. MY truck is going back to the dealership this week to let them try again at repairing something. I am thinking about not accepting the truck back if no repairs are made. If nothing else maybe I can get someone in the management chain to do something. Thanks for the response and please forward the tech support number.
ghost
New member
New update on my issues : After an update to the engine control module and the body control module the Active Fuel Mgmt seems to be activating, that an improvement because before I went months without seeing activation. Time will tell.
On the Collision Avoidance System there is confusion. In first Gap the vehicle in front is ember when less then 3 sec. , but gaps 2 and 3 do nothing. Mechanic says this normal because I do not have adaptive cruise control, just regular cruise control and the manual is silent on the issue, Customer Service does not know what is proper and when I spoke with sales they say the 2 and 3 Gaps should just move the 3 sec. warning out in front more. No wonder they can't fix it, they don't even know what it is suppose to do.
On the Collision Avoidance System there is confusion. In first Gap the vehicle in front is ember when less then 3 sec. , but gaps 2 and 3 do nothing. Mechanic says this normal because I do not have adaptive cruise control, just regular cruise control and the manual is silent on the issue, Customer Service does not know what is proper and when I spoke with sales they say the 2 and 3 Gaps should just move the 3 sec. warning out in front more. No wonder they can't fix it, they don't even know what it is suppose to do.
DaveHow
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I had the exact same problem with the collision avoidance system. I took it into the shop twice only to have them say it's fixed. Nope. So I went online and found a video on the system. The video said to hold the collision avoidance button a few seconds and it may reset. Mine did not. HOWEVER, I turned the truck off and restarted clicking on the warning and braking option. VOILA'! it reset. Not sure how but it did reset. Here is the video I am referring too.
cynistersix
Active member
OP: Mine is now lit up for the first time. Just past the bumper to bumper coverage period which is unfortunate but I'm gonna try resetting and pulling the fuse (F11) to see if it helps. I'll report back if it clears it.
Or disconnect the negative side battery post for a few.
cynistersix
Active member
Pulling the fuse reset the camera and the light is no longer illuminated. This took all of about 2 minutes to "fix".
Faster than Ctlr Alt Del!
I did this the other day and now for the first time I saw a Collision Avoidance sign flash up on the DIC when a truck pulled out from a side road ahead of me. Now that made me feel very happy.
cynistersix
Active member
Took the truck in for the TSB engine recall and some system update. Added the Auto Start/Stop eliminator...
Light is back on in the truck. Time to pull F11 again.
Light is back on in the truck. Time to pull F11 again.
Its not reliable at all. I'll have to do the same.
Well , I’m sure I’m in the minority but I don’t want my vehicle deciding when I need to hit the brakes . If you’re relying on technology to save your skin , makes me wonder who I share the road with . I know who ….. it’s scary . I have not had my 2026 AT4 long enough yet to even find it . In our 2024 Pacifica ( grand kid bus ) I shut the damn thing OFF ! If it pops up on this truck I will do the same .
If you’re not paying attention and something happens , well , you deserve the outcome . I guess I’m an old school type …… not even 60 yet
GMC AT4 Forum Photos
GMC AT4 Forum Photos
