Table 1 shows two common electrical system related problems of the 2026 GMC Terrain.
| Problem Category | Number of Problems |
|---|---|
| Electrical System problems | |
| Adas Blindspot Software problems |
The vehicle has been taken to the dealership at least 4 times. Each time for the same reason: when driving at 65 or higher, it sounds like it's on a flat. My screen also glitches when foot is taken off the break after a stop. The service advisor told me that there was a shortage of mechanics and asked me to bring it back next week (this is the response I have gotten each time). I have asked for a loaner twice and was told that there were none available. Therefore, I had to pay $40 to uber to work. Today, I said that I couldn't come back because it's the same issue and I have to work next week. He then let me speak to a service manager. The service manager drove it (with me in the passenger seat) and heard the sound. He noticed that it was not all of the time and that my steering wheel was a little shifty. When it was finally "fixed" (tires being rotated and some steering update), I was told to come back if I hear it again. I left at about 2pm and heard the sound again, as well as my screen began to glitch when I get off the break after a complete stop. I took a video of the glitching and took it back for both issues. I was told that some bolts were tightened and some update was done to the screen, and if I hear it again come back. On my way home at 4:35pm, the issues were not resolved.
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.