95 of the
4,355 complaints filed about the GMC Terrain
are about the driver-assist systems —
2% of everything owners reported.
The worst model year for it is 2020.
95
Complaints
2%
Share of all complaints
9
Crashes
1
Fires
Driver Assist & Collision Avoidance complaints by model year
Subject: Urgent: Unresolved Ongoing Vehicle Issues - Request for Contact To Whom It May Concern, I am writing to express my strong frustration regarding ongoing and unresolved issues with my vehicle. Ever since I purchased it, I have been plagued by constant alerts regarding various vehicle failures. My vehicle has already been reset and updated twice to address these issues. I just picked it up after it was supposedly fixed at the dealership this past Thursday. However, today, Sunday, [XXX], the exact same warning alerts have started popping up once again. This situation is unacceptable, and I need someone to reach out to us immediately to discuss a permanent resolution. Please contact us at either of the following numbers: Primary Phone: [XXX] Secondary Phone: [XXX] I expect a prompt reply to arrange the next steps. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)
NHTSA complaint #11758926 — an unverified report by a vehicle owner.
Subject: Urgent: Unresolved Ongoing Vehicle Issues - Request for Contact To Whom It May Concern, I am writing to express my strong frustration regarding ongoing and unresolved issues with my vehicle. Ever since I purchased it, I have been plagued by constant alerts regarding various vehicle failures. My vehicle has already been reset and updated twice to address these issues. I just picked it up after it was supposedly fixed at the dealership this past Thursday. However, today, Sunday, [XXX], the exact same warning alerts have started popping up once again. This situation is unacceptable, and I need someone to reach out to us immediately to discuss a permanent resolution. Please contact us at either of the following numbers: Primary Phone: [XXX] Secondary Phone: [XXX] I expect a prompt reply to arrange the next steps. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)
NHTSA complaint #11758926 — an unverified report by a vehicle owner.
The contact owns a 2026 GMC Terrain. The contact stated that after a software update was performed, while driving at an undisclosed speed, the message "Departure Lane Limited due to the Trailer" was displayed. The failure affected the blind spot warning system. The warning light failed to display while approaching a vehicle on the blindside and erroneously operated while there were no vehicles on the side of the vehicle. Additionally, the "Rear Cross Traffic Warning" light was affected by the failure. The vehicle experienced hard braking while there was no other vehicle nearby. The dealer was contacted and diagnosed the vehicle with sensor failure caused by an impact to the sensor. The vehicle was not repaired. The manufacturer was made aware of the failure and referred the contact to the NHTSA Hotline to report the failure. The failure mileage was approximately 11,350.
NHTSA complaint #11755239 — an unverified report by a vehicle owner.
FORWARD COLLISION AVOIDANCE: ADAPTIVE CRUISE CONTROL
adaptive cruise disengaging alert on dash- no cars or weather conditions to induce this. loss of power and bucking on highway( near accident caused) catostostrophic sudden loss of power engine/transmission failure while mechanic driving resulting in car towed back to dealer. loss of power multiple times causing near accidents. sudden jolting at stop light causing car to propel forward requiered both feet on brake pedal to stop. 4 episodes of near collision 1st altert started 04/4/2024 adaptive cruise light on dash 14,700 miles on vehicle 5 episodes continued and now car is still at dealership for emissions failure, loss of power x 4 weeks. ALL PHOTOS OF DASH LIGHTS, REPAIR INVOICES AND VIDEO OF DASH AVAILABLE BUT I AM NOT ABLE TO UPLOAD ALL.
NHTSA complaint #11755131 — an unverified report by a vehicle owner.
The vehicle has had regular maintenance, oil change, and inspection including the brakes. My boyfriend is visiting me in [XXX] from the [XXX]. OnXXX while driving the vehicle the engine started. Making a ticking noise especially during idle and when accelerating in idle. About 15 minutes after the ticking stopped and all of a sudden there's a complete loss of breaks they locked up and the driver was unable to efficiently stop while going down a hill Road. Driver had to use the emergency brake to make the other brakes release and then the brakes from there would not work even though you could stomp on them stand on top of them there was no breaking power anymore. Vehicle was brought into a GMC dealership on the following Monday where they confirmed the issue was a failed vacuum pump connected to the engine and camshaft which is a known safety issue to GMC as part of an ongoing open case they had specialty coverage and bulletins regarding the Tahoe and Sierra but neglected to include the terrain on this issue. Cold the GMC manufacturer in both [XXX] and [XXX] to try and get cost assistance and specialty coverage as the vehicle as well under the mileage requirements but have been giving the push around and zero assistance. The risk to the drivers and passengers lives was significant as we were on the highway for1.5 hrand thankfully the brake lost didn't happen in full during that time. The repairs were completed and paid for in full by the client which should have been covered by the dealership and we are looking for cost recuperation and are now being ignored. Receipts are here to substantiate the claim. The ABS light is no longer on there was no warnings on the vehicle showing any issues or any codes as OnStar was called and diagnostics were received and the diagnostics came back clear prior to this happening, and following the break failure. Lack of codes and warnings is life-threatening and serious. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)
NHTSA complaint #11751119 — an unverified report by a vehicle owner.
I was driving about 55 mph with adaptive cruise control set to maintain a three-car-length following distance. It was raining, and when the vehicle in front of me slowed down, my vehicle did not detect it or slow down as expected. Instead, it continued accelerating, and I had to brake to avoid rear-ending the vehicle ahead.
NHTSA complaint #11750466 — an unverified report by a vehicle owner.
FORWARD COLLISION AVOIDANCE: ADAPTIVE CRUISE CONTROL
I was driving about 55 mph with adaptive cruise control set to maintain a three-car-length following distance. It was raining, and when the vehicle in front of me slowed down, my vehicle did not detect it or slow down as expected. Instead, it continued accelerating, and I had to brake to avoid rear-ending the vehicle ahead.
NHTSA complaint #11750466 — an unverified report by a vehicle owner.
Backup camera stopped working and displays a blue screen stating “service backup camera.” This was an issue when the vehicle was under 3 year manufacturer bumper to bumper warranty and was fixed by dealer at no cost. Now this same issue has occurred again approximately 3-4 years later. I thought at first this was an issue specific to my vehicle but now after doing research I see this is an issue across several GMC Terrian vehicles and other GM vehicles. This issue should be fixed by the manufacturer for all vehicles affected. Vehicle owners should not be responsible to fix faulty parts from the manufacturer.
NHTSA complaint #11745463 — an unverified report by a vehicle owner.
Backup camera stopped working and displays a blue screen stating “service backup camera.” This was an issue when the vehicle was under 3 year manufacturer bumper to bumper warranty and was fixed by dealer at no cost. Now this same issue has occurred again approximately 3-4 years later. I thought at first this was an issue specific to my vehicle but now after doing research I see this is an issue across several GMC Terrian vehicles and other GM vehicles. This issue should be fixed by the manufacturer for all vehicles affected. Vehicle owners should not be responsible to fix faulty parts from the manufacturer.
NHTSA complaint #11745463 — an unverified report by a vehicle owner.
Two issues here. First is that the car will give a danger warning when nothing is there. Sometimes goes as far as slamming on my breaks. Both in drive and reverse. Second is the lane keep assist. It’s like it is working backwards. I turned this all off because it would jerk me out of the lane and into the other lane or off to the sides of the road.
NHTSA complaint #11737214 — an unverified report by a vehicle owner.
Two issues here. First is that the car will give a danger warning when nothing is there. Sometimes goes as far as slamming on my breaks. Both in drive and reverse. Second is the lane keep assist. It’s like it is working backwards. I turned this all off because it would jerk me out of the lane and into the other lane or off to the sides of the road.
NHTSA complaint #11737214 — an unverified report by a vehicle owner.
Two issues here. First is that the car will give a danger warning when nothing is there. Sometimes goes as far as slamming on my breaks. Both in drive and reverse. Second is the lane keep assist. It’s like it is working backwards. I turned this all off because it would jerk me out of the lane and into the other lane or off to the sides of the road.
NHTSA complaint #11737214 — an unverified report by a vehicle owner.
This is a continuation for NHTSA campaign number 11711615. While an additional NHTSA complaint has been filed for the power train, this focuses specifically on design failures in the braking system. Our vehicle experienced a highway failure of the fuel pump, but due to the nature of a powertrain failure the car could not be put into neutral, only remain in park. The car was stranded in the middle of the road. As a AWD vehicle it similarly could not be towed as both wheels were fully locked. Tow informed us that there should be a manual release under the shifting column, however, this design safety feature had been removed in the 2024 iteration. The car was stuck on the road behind a blind turn on a somewhat busy road with vehicles typically traveling between 25-50 mph. The failure of a manual override for neutral and braking is a critical design failure that can lead to major accidents and death in the event of engine or transmission failure. There were no warnings, nor instructions or ability to get the car off the road.
NHTSA complaint #11734066 — an unverified report by a vehicle owner.
The head unit quit working around 98k. The head unit is the radio, and screen which includes the back up camera. From what we have been told and find online, this is a known problem with them and affects other models as well. For the most part the head unit doesn't work but once in a while, once a month, it comes on but shows the Chevy logo on the screen which is odd because it is a GMC. Once you turn the car off, it will be gone again until it decides to come back. We took it into a dealer who tried to hook up to it and reprogram or update it, but he had no luck. Now we are without a backup camera that is a safety issue. I do not know why this isn't a recall as it is well known about issue.
NHTSA complaint #11733049 — an unverified report by a vehicle owner.
The engine light came on while driving, saying “engine power reduced”. It barely accelerates, RPMs go over 5, it chugs when driving. Taken to an independent service center.
NHTSA complaint #11713477 — an unverified report by a vehicle owner.
The system that failed was the brakes, The car is availble for inspection. My saftey and others was put at risk due to not having brakes to stop. The problem has been confirmed by a dealer as a master brake cylinder failer The vehicle has been inspected by the dealer. There were warning lamps, message and other symptoms of the problem prior to the failure. They first appearead on December 4 2025
NHTSA complaint #11710663 — an unverified report by a vehicle owner.
Top of roof pops when you shut car door, Leaking either transmission fluid or oil, Left turn signal doesn't stay engaged when turning, Side mirror warning lights randomly go off when no car is around. Car is not shifting correctly when driving
NHTSA complaint #11709231 — an unverified report by a vehicle owner.
Top of roof pops when you shut car door, Leaking either transmission fluid or oil, Left turn signal doesn't stay engaged when turning, Side mirror warning lights randomly go off when no car is around. Car is not shifting correctly when driving
NHTSA complaint #11709231 — an unverified report by a vehicle owner.
I was driving (roughly about 30 MPH) when my automatic braking kicked on and caused my tires to squeal to a halt. There were no other cars around me (thankfully) - otherwise I would have been rear-ended. Right before it stopped, it flashed the warning lights for a quick second. I wanted to report this issue in case others are experiencing the same problem and to hopefully help prevent it from happening to someone else. Very scary and could cause a serious accident. I turned off all of my automatic brake settings after the incident, as I believe it is faulty and don't want to risk it happening again.
NHTSA complaint #11707983 — an unverified report by a vehicle owner.