2020 GMC TERRAIN Unknown Or Other Problems

I own a 2020 GMC Terrain with approximately 110,000 miles. While driving in winter, the vehicle suddenly lost cabin heat and defrosting capability. The temperature gauge began fluctuating and the cooling fans continued running after the vehicle was shut off. A mechanic diagnosed the cause as a cracked radiator that allowed coolant to leak out, which is a known frequent failure on this model. Because the heater stopped working in sub-freezing temperatures, this created a safety hazard due to lack of defrosting and heat while driving. The failure occurred without warning, and no coolant warning light was displayed before the heater stopped working. The vehicle was not overheating at the time, but the loss of heat and defrost made winter driving unsafe.

The rear backup camera in my 2020 GMC Terrain failed. I first noticed and noted that the image was 'cloudy' on 5/3/2023, and it became very bad by 1/22/2024. On 7/1/2024, the image stopped working completely, replaced with a blue screen on the dashboard screen. I ordered a new camera and replaced it myself on 8/1/2024. Because the dealership did not mention any safety effects or recalls, and instead quoted me a very expensive repair estimate, and the vehicle was out of its 3 year warranty, I assumed it was my responsibility to repair this feature. However, I have seen recent news articles where other vehicles have been recalled by NHTSA for similar problems with backup cameras.

My a/c went out within 2 years of having the car in 22’. In 2025 i have had nothing but problems, the radio will go out when im driving for about 2 hours and it resets, the screen goes black, music stops, navigation stops and then it turns on like nothing happened. It happens everytime I drive 2+ hours. Back in September of 2025, I was on my way to work when I was stopped at a red light, it turned green and then my brakes locked up and I couldn’t drive my car had shut off, and wouldn’t come back on. I was stuck in the middle of the road not knowing what happened as the car had driven fine up until i stopped at the red light. Then tonight November 21,2025 around 0315 I was leaving work, I started my car, my car threw up a message that...

I was driving on the highway below the speed limit when I heard a pop that sounded like a balloon and instantly the sound of wind getting into the car. I pulled over and found that the sunroof was rapidly shattering. I did not see a rock that had hit it. Maybe the tempered glass just exploded. I was not driving very close by any other vehicles at the time, but was on the highway.

The Vehicle Identification Number for this vehicle is not recognized in the NHTSA program. From Online vehicle registration Oahu Hawaii

Back up camera does not work. It shows a blue screen and says service repair needed.

The bolts fell out and the bracket that holds the drive shaft in place fractured while driving.

My backup camera in my 2020 vehicle has failed twice. Once was covered under manufacturer's warranty, and it then failed again 14 months later, which is not covered under warranty. As explained by the dealer, a parts warranty is 12 months if covered under manufacturer warranty and 24 months if paid for by the owner. Different warranties for the same part? Additionally, there is a service bulletin out about this issue as MANY other owners are reporting the same issue. The camera parts are being damaged by "water intrusion". There is NO rust or damage that would be contributing to this, thus it appears to be a manufacturing defect. There is no way I should have had to replace this part twice with only 40,000 miles on the vehicle. (first time at 24,000 miles, second time at 38,500 miles). I feel that the manufacturer should be fixing these as they...

Every time it rains, the floorboard of my car is soaking wet. I took it to the dealership, and they stated the leak is coming from inside the firewall. I have only had this vehicle for 2 years and just recently moved to a house without a garage. Now that I am just now noticing it, I am wondering if it was like this when I bought it, but I am only noticing it now that I do not have a garage. They want to charge me over $1,000 just to take apart the dashboard to find the leak and that is just insane. There is no telling how much mold, rust, etc. could be in my car from this leak.

My car sunroof drainage system is not draining properly and GMC won’t see me for a month. There’s an excessive amount of water that’s pooling in the rear passenger floorboards buckets of water.

While driving my vehicle, check engine light came on. Then, my car proceeded to flash about 4 warnings on the dash, Fuel Level Low (had half tank of gas), Engine Power Reduced, Service ESC, and Service Transmission. My vehicle shut itself off while driving 55 down a main highway and put itself into park. Forcing me to pull over and be stranded on the side of the road. In the way of other cars, with no way to get out of the way. I then had to shut car off, wait, and start it back it up. However, after the first time this happened, I cannot drive my vehicle more than 15 to 20 minutes without it doing this to me over and over again. To make matters worse, I am 37 weeks pregnant, and the last thing I need is to be without a car. I also had just...

On 4/10/2023, I took my vehicle to a local GMC dealership because it was stalling and didn't have any power. Upon accelerating the vehicle it would stall and take off at a high speed. The dealership has had my vehicle periodically from April 2023 and it presently sets at the dealership because they ain't getting a code, But after the dealership drove the truck for over 200 miles, they were finally able to duplicate the stalling yet are not able to diagnose the problem!! This vehicle is very dangerous to be on the road and I have almost gotten hit twice and I'm not driving the vehicle anymore at this time. I have previously reached out to you all and I would be most thankful if you could get in touch with me. Thank you

I was driving approximately 75mph on the interstate. 3 hrs into my trip I started feeling hot so I turned the a/c up. In my peripheral vision I saw orange and thought a car was beside me on fire. Immediately I realized it was my vehicle. I immediately slowed and came to a stop. I put it in park and opened the door. By the time I started to exit there were flames higher than the rear windows. A car that was behind me stopped. They said about a mile back there was a spark under the car by the rear tire. Then it went up in flames.

My 2020 terrain is now at 33k+ miles, I have had repeated instances with my car not accelerating properly. I would be at a full stop try to start to accelerate and not move push down a little further on accelerator and start crawling forward. I would move approximately quarter mile before the vehicle would jerk and accelerate very quickly to a speed well over where it should go to. I.e. I know because I’m starting in traffic I’m not trying to take off at thirty but when the jerk happens I can be jolted to 40-45 mph. The other issue is people behind you don’t realize what’s going on and I have been hit almost twice thankfully they were able to avoid me by going around. No warning lights have come on. This last insistence not only could I not accelerate, but cruise did not want to turn on,...

Screen system prompts to accept terms of service while moving. This is unsafe and the system should know it is in motion. Unsafe programming, require manufacture to only prompt when system is at reset. Require OTA reprogramming.

My service brake assist light came on and then within seconds my vehicle then said engine power has been lowered and my vehicle pretty much shut down no steering no brakes couldn't do anything. Took it into the repair shop and my vacuum pump has shattered and now damaged my camshaft. I am aware there's been many other vehicles recalled with GM's vacuum pumps and I'm not sure why my year and model has not been included when it's doing the same thing and not to mention I have seen countless other cases of people saying same things happen to them with their GMC terrains.

VEHICLE HAS 56801 MILES AND AIR CONDITIONING COMPLETELY WENT OUT. i HAVE ALSO REPLACED WINDSHIELD WIPERS TWICE IN 6 MONTHS. THIS IS MORE THAN ANY OTHER VEHICLE i HAVE EVER OWNED (i HAVE HAD THE VEHICLE 1 YEAR NOW)

The engine "Auto Stop" feature can have enough of a delay to allow the accelerator to be pressed as the engine starts causing it to lurch forward rather than accelerate smoothly. It also can cause a delay when pulling out into heavy traffic. There is currently no way to temporarily or permanently defeat the system on this GM model according to GM service department. Though I am sure it is operating as designed for certain owner driving styles and traffic conditions this can be a serious hazard. Car makers should be required to either disable the feature permanently by owner request or have a method for the owner to bypass the system. With less than 250 miles I have experienced 2 incidents of almost hitting the car in front of me from a stop and 1 of almost being hit pulling into heavy traffic from a stop. I see many...

Dash had gone black intermittently, did not know what speed I was going. OnStar called oor phone multiple to notify us that our airbags we're offline for ten days no warning light on dash until one to two days later . Took to service was informed that gear shift control, engine control module, passenger presence module and airbag sensor needed replaced. All within a month of purchase of said USED vehicle. Vixed under warranty. Then another monther later, got warning on dash saying "conditions not current for shifting", park break light came on, and a p in a yellow circle with a wrench under it came on. Serive did fix vehicle, but could not verify message on dash about conditions not favorable... Also recalibrated breaker. Complained numerous times to dealer about these issues and was told "live with it".

While driving instrumental panel and infotainment panel completely blacked out for no reason at all. This is the second time in two days this has happened.

Instrument panel and infotainment system panel completely blacked out while driving vehicle

I had an incident this morning when I put my car in park position it remained in reverse. I took it out of park and put in drive then I put forward but the vehicle still remained in reverse. I turned the vehicle off and it still remained in reverse. Ali controls on infotainment panel was inoperable. ( example: I couldn’t turned off or turned radio).

After starting my vehicle on May 28, 2021, the infotainment screen was pink and green with lines. The radio was playing loudly, and I had not previously set it to that volume. Additionally, the volume control button did not work. I headed to the nearest GM dealer, and I did not attempt to turn off the screen. A service representative said I needed an appointment, and I could not be seen until one day during the next week. I needed the turn-by-turn navigation, and I did not know if the issue would worsen or cause other issues, so I asked for a rental vehicle. My vehicle had accumulated less than 10,000 miles, and I have an extended warranty. I was told the vehicle has to be diagnosed before a rental is approved, and their loaner vehicles were out for two and a half weeks. Every dealership I called stated I...

WHEN EVER I GO TO TURN MY STEERING WHEEL AND I GO TP PUCH IN THE GAS PEDDLE THERE IS A VIBRATION DURING MOTION.

PURCHASED NEW 2020 GMC TERRAIN W/7MILES. LEFT DEALERSHIP ON MY WAY HOME, AND WITHIN 20 MILES, RECEIVED A MESSAGE ON DASH-> SERVICE - ESC - DISMISS. CHECK ENGINE LIGHT FLASHED SEVERAL TIMES, AND THE SUV SLOWED DOWN AT LEAST 10 MILES FROM 65MILES PER HOUR. AFTER ENGINE LIGHT STOPPED BLINKING, I CONTINUES HOME AROUND 30 MILES MORE WITH NO MORE PROBLEMS. CALLED MY SALES PERSON THE NEXT DAY, AND HE DID NOT KNOW WHAT ESC WAS. (ELECTRONIC STABILITY CONTROL) HE CALLED ME BACK AND INDICTED THE VEHICLE MAY NEED A SOFTWARE UPDATE. I TOLD MY WIFE, WHY WOULD A DEALERSHIP NOT CHECK ON VEHICLE SOFTWARE UPDATES BEFORE RELEASING VEHICLES TO THE NEW OWNERS, PRIOR TO LEAVING THE DEALERSHIP. THIS IS CALLED, "BEING PROACTIVE." WE WERE ON THE HIGHWAY LEAVING THE DEALERSHIP AFTER PURCHASING THIS NEW SUV.

THE AC SYSTEM PRODUCES A TOXIC CHEMICAL SMELL CAUSING THE DRIVER AND/OR PASSENGER TO OPEN THE WINDOWS IN ORDER TO REMOVE THE TOXIC ODOR. THE SMELL IS INTERMITTENT AND CAN BE MODERATE TO EXTREMELY POTENT.THE VEHICLE IS USUALLY IN MOTION WHEN THIS OCCURS AND CAN HAPPEN WHILE DRIVING LOCALLY AND ON THE HIGHWAY. THE LAST TIME THIS HAPPENED WAS AUG. 1, 2020. I HAVE HAD THE VEHICLE SEEN AT A LOCAL GMC DEALER 3 TIME SINCE JUNE, 2020. THE VEHICLE WAS NOT DRIVEN BETWEEN MARCH AND EARLY JUNE DUE TO THE PANDEMIC.

THE COMPLAINT I HAVE IS THE INSIDE FRONT OF THE CAR IS TOO SMALL AND I CANT REACH THE GAS PEDAL EXCEPT WITH MY TOE. MY FOOT KEEPS SLIPPING OFF AS I AM DRIVING. I HAVE TO HAVE THE SEAT WAY UP OR I CANT REACH. I AM 5 FOOT TALL WOMAN. THIS IS A RIDICULOUS THING THAT I HAVE TO PUT UP. I DROVE IT FOR 10 MINUTES AND DIDN'T REALIZE IT. I ASKED FOR A PEDAL THAT IS LONGER AND CLOSER TO THE FLOOR AFTER I HAD BOUGHT IT AND SERVICE PEOPLE TOLD ME THEY DON'T HAVE ANYTHING TO DO TO FIX IT. THEY ASKED IF I HAD A BUTTON TO ADJUST IT AND I DON'T. ITS ON THE EXPENSIVE ONE. THIS SHOULD BE ON ALL VEHICLES FOR SAFETY. I WANTED TO GIVE IT BACK BUT THEY NEVER HELPED ME. I HAVE 1100 MILES ON IT .IT NEW...