Electrical System Problems of GMC Terrain - part 1

Break assist light comes on and brakes stiffen suddenly with no warning. Happened 6 times now in a 3 year span. Gotten it "fixed" each time but it keeps happening.

See all problems of the 2020 GMC Terrain 🔎.

Screen went black on 3 different occasions, since purchasing vehicle.

See all problems of the 2022 GMC Terrain 🔎.

GMC Terrain with 12,564 total miles had experienced an engine failure. Under normal driving conditions, the car was sluggish and would not accelerate properly when pulling out into traffic or when getting on the freeway/interstate causing fear for driver safety and causing traffic slowdowns or congestion with a significantly increased risk of crash. While driving to work, the vehicle service engine light turned on and displayed "reduced engine power". Upon investigation the dealership found codes p0011, p0014, p0016, p0017, and quoted "cylinder 4 intake rocker had fallen off and laying on head, found excessive debris and metal material around rocker 4, found cylinder 2 intake rocker to be worn sideways. Found heavy damage to intake camshaft. Removed oil filter - found excessive metal in oil filter". Secondary issue, infotainment screen would randomly flash bright white on the right half, causing a major driver distraction. Engine, turbo, and infotainment system were all replaced, and vehicle returned 11. 06. 2025.

See all problems of the 2023 GMC Terrain 🔎.

Backup camera not working and has a blue screen. The camera was replaced. The fuses & wires were inspected and the screen remains blue.

We have been keeping up with all maintenance and oil changes. We have only driven the car for less than a year. At time of oil change; the oil has been low, resulting in over oil consumption; requiring an extra quart of oil to be added between oil changes. When we purchased the vehicle, there was an strong exhaust smell; the shop that we bought the vehicle stated there were no issues and we have taken it to them multiple times an hour away from our home. The car completely shut off while my minor son and I were driving. Placing both of our lives at risk! it would never start back up. Now the car has seized and requires an engine replacement. It is sitting at a local garage while we wait for the dealership to help us, to no avail.

See all problems of the 2017 GMC Terrain 🔎.

Sunroof/moonroof/sunshade and frame leaking for 2nd time.

Back up camera just started showing a blue screen with message that stated service back up camera. No accident, has not been to dealership. Just started 8/15/2025. No warning given.

See all problems of the 2019 GMC Terrain 🔎.

Incident 1: pulled out from stop sign car made funny noises, light came on said it couldn't shift to drive. Had towed to dealer. They said couldn't find issue except it was quart and a half low of transmission fluid. The car had approx 3,500 miles on it. Incident 2: for about two weeks when pulling out felt like it was skipping but didn't feel like transmission. Felt like over powered. Then it done same as incident 1. Pulled out made noise would not move. Notice that is couldn't shift and check engine light came on had it towed again. Approx 6,300 miles on it. They then said it was very low on transmission fluid and they did find a small hole in hose. Danger is pulling out and it just stops in cross traffic and won't move could easily be hit. It is very scary to drive not knowing if or when it is going to happen. I have no current invoice on vehicle as it is still in shop.

Vehicle has had check engine light and engine reduced power flicking on and off for months, randomly reducing power on highway or nearly causing accidents. Brought car to GMC dealer, they said it was underboost code and needed new turbo. Paid over 7,000$ for repair. Next morning, same issue still was happening. I believe my vehicle has emissions recall issue “n192271200 charge air cooler disconnect at throttle body” but gm has not properly attached my VIN number for this recall repair. I have poured thousands into repairs out of pocket and the same issue still persists. I believe strongly the recall emission issue is the problem and should be on my VIN. Vehicle has been to dealer 3 times in the past 2 weeks, issue has not been fixed. Improperly diagnosed, random repairs made not fixing actual issue.

A little over two weeks ago we were going to sidney to get groceries. It was hot that day so we turned the a/c on. Fog started coming out of the vents, it looked like we turned on a fog machine! a few days later we were going to town, my daughter got in and the whole driver's side floor was full of water. There was so much of it we had to get the shop vac out to suck it up. I called the dealer where we purchased it from because it still under warranty. Their shop guy was out for the week so they scheduled me an appt for the following week. By this time my speakers aren't working, my signal lights dont make any sounds when I use them and the floor is soaked again. On August 5th we took the car into high plains and left it. They said they worked on it for 4 hours and fixed the problem, some drain line was plugged with sludge and so the water knocked out a module or amp. I thot everything would be covered but then they said I'd have to pay because all of a sudden a mouse had causes that line to get plugged. I asked them for pictures because im turning it into my insurance company, and they said they would send them. They never have I requested the pictures 2x, once with patrick the shop manager and then with jeff presser, owner. Still today, nothing. Meanwhile yesterday here comes all the water on the floor again. We use this vehicle to haul my grandson to his therapies and medical appointments. He has cerebral palsy and has severe respiratory problems that requires him to be on oxygen. Now were worried that mold has started growing because even though were sucking up the water, the floor pad and carpet are still wet. I went online and have seen numerous people complaining about the same issue for years with these GMC Terrains, why hasnt there been a recall or national warning on this faulty problem?.

See all problems of the 2024 GMC Terrain 🔎.

Component affected: service brakes, hydraulic – brake vacuum pump summary of the problem: I am reporting a serious safety issue involving the brake vacuum pump on my 2018 GMC Terrain. The brake pump failed catastrophically ("blew up"), resulting in a sudden loss of braking power. This occurred without warning and posed a significant risk to my safety and others on the road. We were traveling to vacation in florida and thankfully had just gotten off the interstate. Details: the failure caused the brake pedal to become extremely hard to press, and the vehicle required a much longer distance to stop. We experienced no brake at the brake booster and a blown vacuum pump is due to a faulty vacuum pump which is a known issue for this model. Fortunately, no accident occurred, but the situation could have easily led to a collision. A certified mechanic confirmed that the brake vacuum pump exploded and needs to be replaced. I have incurred significant out-of-pocket repair costs due to this issue. We had to uber to our vacation room, get walmart plus to have groceries delivered to our room. We had to have uber eats deliver other supplies. We have had to walk to various places for dinner and entertainment because avis and budget had no vehicles available to rent and enterprise was closed as we arrived on Saturday afternoon. I have checked for recalls and service bulletins using my VIN, but none are currently listed for this specific issue, despite similar problems being reported in other gm vehicles. Request: I urge the NHTSA to investigate this issue further. The failure of a critical braking component without warning is a serious safety concern. I believe this may be part of a broader pattern of brake system failures in gm vehicles and should be addressed through a recall or safety campaign. Also, the estimate for the repair is $2,500 so any reimbursement would be greatly appreciated. We just received this estimate but I can provide it at a later date.

See all problems of the 2018 GMC Terrain 🔎.

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).

See all problems of the 2021 GMC Terrain 🔎.

Tensioner issues keeps breaking the timing chain. . Replaced twice at own cost. Fuel pump/ loss of power while driving. Back up camera doesn't work sometimes. Screen goes black. If key is left in the ignition it starts itself. If you try to use a car charger for a phone the ac shuts off and a "systems error" message pops up. This happens alot. It's an ongoing issue since I bought the car in feburary this year.

See all problems of the 2014 GMC Terrain 🔎.

The contact owns a 2018 GMC Terrain. The contact stated that on several occasions while driving at various speeds, the infotainment system screen and radio inadvertently switched stations from am to fm. On other occasions, while driving and using the gps system, the screen went blank. The contact stated that on several occasions the screen was turned off, and on other occasions, the screen was turned off and on however, the failure was temporally fixed. The vehicle was not diagnosed of repaired. The manufacturer was not notified of the failure. The failure mileage was approximately 77,000.

Back up camera service notice.

5. 25. 2025 - car shut down while at a busy intersection. Called amherst police due to location and how dangerous the intersection was. Family member needed to jump start the vehicle. Vehicle started before police arrived. Drove home. Called police to let them know we were no longer at the busy intersection. 5. 26. 2025 took out battery to check charge at auto store - tested good - 82%. Re-installed battery went to get gas thinking that may be the issue, low on gas, not the case the car wouldn't start at the gas station. Family member needed to jump start the vehicle again. Drove home, called dealer, taking to dealer next week 6. 4. 2025 due to availability of service. There were no warning lights prior to stalling out both times. This is very dangerous. We are afraid to drive this GMC 2020 Terrain.

Abs brake problem and have tried to get it repaired for over 3 months and cannot seem to be able to get the part and call gm with no help. Can not tell me when or where to buy the part. Nobody seems to be able to get a new part and no help from gm. If there is this many problems that there is no part left available it should be a national recall.

The contact owns a 2025 GMC Terrain. The contact stated while driving at an undisclosed speed, the infotainment system displayed a blank screen. The contact pulled over to the right side of the road into a gas station and turned off and restarted the vehicle, and the infotainment system displayed a message "update failed - see dealer to restore system". The dealer was contacted. The vehicle was not taken to the dealer or an independent mechanic to be diagnosed or repaired. The manufacturer was not notified of the failure. The failure mileage was unknown.

[xxx] once again while diving down the road 45mph Terrain once again goes in to park ,I was lucky the lady behind me wasn't to close . Also I contacted onstar when I was able to get vehicle moving at the store . . I told her what happen she ran diagnostics while parked at store said there was no codes I let onstar know this has happened several times. . I had no warning, no indication, no lights came on. And I also let her know that this same vehicle was still stalling I was at intersection and the auto/stop is always on it will not let you bypass or default took it to dealership who I bought cpo back when it first would not let me turn it off cause its stalls at stop signs ,red lights etc crazy thing is if you turn the ac on it cranks up , if you hit the door unlock it starts. . . Thats not normal GMC knows that the dealership whom sold me cpo that wasn't the misleading is beyond crazy. . Gsm cussed me out it comes with life time warranty but when I had it towed right after I bought it 2 months . . I was talking about what the mechanics had said that this vehicle was in prior flood and accident GMC onstar has a different VIN then the one that on the vehicle. . The doors are not original I can see the inside of steering wheel and on dash where they said air bags were deployed and they did a [xxx] job hiding it . . . I paid over 32k for this 2020 Terrain that was advertised as cpo with 1 owner in florida they showed me a fraudulent carfax, I pulled up my own and it came from new york . . This vehicle is not safe to drive but I dont have any other options. . I have made complaint with both GMC and my finance company whom also wrote complaint on dealership and the told me I could rewind the loan but when I told dealership I knew that they sold me a vehicle that was not cpo and what I learned he came at me at dealership infront of workers and customers . . The vehicle just going to end up getting myself killed or someone else. . Semi had to run off road to avoid hitting me information redacted pursuant to the freedom of information act.

Vehicle every other morning shows issue with blind spot assist. It keeps popping an error message and it has happened since I purchased it new. Took it multiple times to dealership and they cannot recreate issue. So it's been an issue since I bought it now.

Vehicle was running but transmission was in park. Suddenly on screen in front of driver this message appeared: brake system failure 43mph top speed warning service esc. Vehicle was not moving. Engine was running but vehicle was in park. I had to drive it home. Very difficult to stop. Brake pedal vibrated violently. Very long stopping distance even at 20mph. I had the vehicle towed to the dealership from which I had purchased it. I bought this vehicle on 25 Nov 2024. Right now its mileage is 3757. Obviously my safety and that of others was put at risk. The service department at the dealership has not communicated with me at this time. There was no prior warning nor were there any prior symptoms of this problem. It occurred very suddenly.

The contact owns a 2022 GMC Terrain. The contact stated that while operating the vehicle, the service message was displayed, and the audible turn signal became inoperable, along with the collision warning and the on-star feature. The cause of the failure was not yet determined. The dealer was notified of the failure, but no assistance was offered. The manufacturer was not yet contacted. The failure mileage was 22,000. The VIN was not available.

When accelerating, the engine revved up, switched itself from drive to park, resulting in complete loss of control and the vehicle coming to a sudden stop. The car behind narrowly avoided a rear-end collision by swerving around me. The malfunction indicator light came on for the first time, and the vehicle would not switch out of park. After turning the ignition off and on again, the vehicle would switch out of park. The GMC service inspector ran diagnostics and found fault codes related to the transmission valve components that must be replaced.

At stop light turning right, the car stalled, cut on and cut back off, cut on and back off with about 30 cars behind me. Sputtering. On the dash board it said “engine power reduced”. I had to be pushed out a main highway by police, and thankfully my 6 month old daughter wasn’t in the back seat. I have had this car 12 days with 48256 miles on it. I’m extremely concerned with the safety of this car. And when towed was leaking gas like fluid.

Today is [xxx]. 3 days ago my infotainment system my plug-in lighter charger all of them that's in the vehicle and my rear windshield wiper and my blinkers all went out at the same time. I had a licensed mechanic that has the fuse checker tool, checked every fuse that he can see under the hood and on the inside of the vehicle and all the fuses lit up. I then went to o'reilly's auto parts here in highland park michigan bought the savannah long life two pack bulbs for the rear blinkers and they still did not work they would not come on the brake lights would not come on nothing comes on. I then told a gentleman named frank at that o'reilly's about the issue about how all those components went out at the same time and he said there was currently a recall about those issues on my year making model of my GMC Terrain which is a 2017 I cannot locate that recall. The only recall I can locate is the one that describes the high beam on the headlights and that is it. So I don't know where that recall is he's talking about I don't know anything about fixing cars I just need some answers. I'm hoping someone will be able to locate the recall that he's talking about so I can have my vehicle looked at and get the issue resolved. Information redacted pursuant to the freedom of information act (foia), 5 u. S. C. 552(b)(6).

The contact owns a 2018 GMC Terrain. The contact stated that the transmission was shifting gear erratically. The contact stated that the doors were locking and unlocking independently, and the instrument cluster was blank. There was an abnormal beeping sound coming from the vehicle. Additionally, the contact stated that while at a traffic light, the auto start/stop feature delayed to respond. Onstar was alerted, but the contact declined to perform the service. The contact was in contact with the independent mechanic who sold the vehicle, but no assistance was provided. The local dealer was contacted. The vehicle was not diagnosed or repaired. The manufacturer was contacted, but no assistance was provided. The failure mileage was approximately 130,000. The VIN was not available.

Onstar module failure its backordered across the entire country, its only reasonable to assume it's a problem. Online information I've seen is it's an issue with a lot of vehicles.

Service parking brake comes on, steering reduced. Problem reoccurring often, but intermittently. Actuators malfunctioning causing many sensors to fail off and on. Huge safety concern for myself, my riders, and anyone else on the road. When this happens my car has to “think” to move unless you clear the pop up message. Check engine light comes off and on at its leisure. When steering reduced comes on the car will not move until ready. This is clearly affecting electrical things as when I shut power off to other supplies it sometimes becomes more frequent as well as less frequent. The car does not understand what to do as its computers are confused at what the problem is, as the problem does not consistently happen. I have print outs of one time I caught it with failing actuators. I refuse to go to the dealership as I’m told “OH the problem isn’t happening now. ” which negates safety of all people on the roadways. You’re more than welcome to inspect. Though I will be present as I refuse to be told there’s no problem. As previously stated this happens when it wants to happen, but again I’ve caught the issue and can supply information.

My vehicle began jerking, shaking and kept shutting off in a highway intersection. I looked on the ground after coasting into a gas station to find oil leaking from under my vehicle. I've never had an oil leak and it caused my starter to go and I've had to replace the camshaft sensors all within the same week. It appears the rear seal went after the cold streak we had. I need my vehicle to take my mother to treatments, etc. Is there any recalls on this?.

See all problems of the 2015 GMC Terrain 🔎.

Vehicle has not recently been inspected, backup camera has recently gone out leaving only a blue screen with "service rear vision system" to my knowledge nothing has happened to the unit that would cause this. Regular day to day driving, there was nothing that would have given me any notice that this would be happening.

Blue screen with the message "service rear vision system".

Backup camera stopped working, giving me a blue screen.

My Terrain has a light that has been coming on for a couple months. Service brake assist. I took it to the dealer after my brakes locked up and about $800 after getting it fixed the light continues to come on. The forward collision light comes on every time I start the car. More the check engine light came on and says engine electrical system. What the heck is going on? I love this car and take very good care of it but I feel like the $800 that I just spent was a waste. I fear that I will get in a wreck like when the brakes totally locked up and I couldn't press on them.

Reduce spreed unknown if related to fuel pressure regulator since repaired twice told could be to service bulletin. Warning lights keeps appearing while driving at a speed of 40 to 50 mph.

See all problems of the 2010 GMC Terrain 🔎.

My esc randomly comes on. Service parking brake message comes on intermittently. Messages pop a up saying steering wheel assist limited, drive with care. Again, all of these are intermittent but when they happen my steering wheel locks up. Even mid turn. Being intermittent it doesn’t always happen and weather seems to affect when it happens, or that’s a coincidence.