There are 5 owner-reported electrical system complaints for the 2021 GMC Terrainin NHTSA's database. These are unverified consumer reports and may not reflect confirmed defects.
Driving my vehicle with no warnings, messages, or symptoms on adaptive cruise control Sunday [XXX] on [XXX] in Michigan. I changed lanes into the right lane when the vehicle abruptly, without notification, and with force, caused braking that unexpectedly and dangerously slowed the vehicle then released braking before doing the same a moment later. Vehicle was pulled off the road onto the shoulder without an accident, thankfully nobody was behind because they would not have been able to stop in time before hitting my vehicle and I assume the brake lights weren't activated since I did not press the brake pedal either time the vehicle was abruptly slowed causing audible noise of traction loss due to skidding. Vehicle engine would function but parking brake remained active leaving vehicle unable to change gears and transmission warning showed on instrument panel. Vehicle towed to a Chevrolet dealer in Grayling, Michigan where it remains and would be available for inspection. Dealer shows transmission as the cause and in need of replacement. Vehicle has been maintained at GM shops since original ownership. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)
I purchased the car August 2024, I have had it for 4 months and while driving down the road a large fuel tank pops up stating low fuel and the car comes to an abrupt stop.The 3x the gas tank was never low. Parking brake comes on and car doesn't not move. All lights on dash come one. It has done it 4 times and thankful each time I was in a 30 mph zone. If I was going 55 I am sure the result would have been bad. The car last did it on December 29, 2024 and has been in the dealership for 3 weeks now and they cannot fix it. I told them 3 days into my purchase I wanted a full refund and they denied me. ?? I had that right I am still fighting with them to take it back because one of these times I am going to get in a bad accident. I don't feel safe in the car and I told them each time.
Recently I have noticed that the back brakes squeak and sound like they are grinding when backing up. Also every now and then the information screen will go black for a while then turn back on could be a few seconds or several minutes. 23,900 on car
While driving my vehicle and talking on the phone, the radio screen went black. Bluetooth or nothing in connection to it was working. After about 2 hours it came back on. I was told to bring to dealership to be checkout, but it came back on. I'm going to take it to the dealership. My vehicle has 13,000 miles on it.
I dropped my son off at school and he mistakenly took my car keys into school with him, and somehow I was able to drive all the way home, 4.5 miles, with no key in the car and no warning to stating the remote wasn't in the car. The issue with this is if I'd driven further, perhaps to another state, or even driven somewhere at night, I would have been stranded once I turned the car off. There was no indication that the remote wasn't in the car, and the car never cut off. I only knew the remote was gone once I arrived home and turned off the ignition. That's when the message displayed that the remote wasn't in the car. I had to call an Uber to go back to my son's school to get the key. This could have been a disaster had I driven further or not had the funds to get back to my son's school. Not to mention if a car thief had someone occupied my car and driven off in it. They could have gotten as far as they wanted (or gas would allow) before the car shut-off as long as they didn't turn off the car. I stopped at stop lights and stop signs and the car just kept going. The issue should be looked into and addressed immediately. This just occurred yesterday. The vehicle has not been inspected and this was the first time anything like that has happened. I normally receive a warning message if my remote isn't in the car even if it's just in the house. This is clearly a defect that needs to be fixed.
Complaints are unverified consumer reports submitted to NHTSA. A high complaint count may reflect vehicle popularity, not defect severity. Data sourced from NHTSA public records.
Data synced from NHTSA on Apr 26, 2026