Mileage when the problem started
Owner reports
Selected complaints filed with NHTSA by 2019 GMC Terrain owners, lightly cleaned up (personal details are redacted by NHTSA).
*Service trans, check engine, stabilitrak, gas light, would not come out of 1st gear, stalled, started back up and jerked on the way to dealership, locks were flickering, lights would not light up for the PRNDL, shift to park message on, and vehicle would not start back up when pulled into service drive. *would not shift out of 1st gear while in traffic, vehicle stalled in traffic, vehicle jerked whi9le driving. *Confirmed by LaFontaine of Ann Arbor, MI *Vehicle inspected by LaFontaine of Ann Arbor, MI Service trans, check engine, stabilitrak, gas light, would not come out of 1st gear, stalled, started back up and jerked on the way to dealership, locks were flickering, lights would not light up for the PRNDL, shift to park message on, and vehicle would not start back up when pulled into service drive. TAC Case # 9-6556499036. …
The car failed to shift into gear. Message displayed, "transmission unable to shift" ,"2 gears selected " or "service transmission". Issued started in June 2022 while in drive thru line, when shifting from park to move the car would not shift. Had to turn car off for about 10 minutes and car was able to shift and drive normal. Check engine light came on about a week later and had checked for code p07b5. A couple of days later, light went back off. About 3 days later getting ready to leave home and car would not shift into gear again but turn car off and back on a couple of times and car shifted and drove normal. On July 13 2022 was driving in traffic and message displayed, unable to shift and service transmission. …
I bought this Terrain brand new from Betten Baker Chevrolet in Muskegon Mi in 2019 with 500 miles. That same year we had transmission Slippage causing it to slip out of gear then slam back into gear while driving. I took it to the dealer to have it looked at. They did nothing and informed me it was known by the manufacturer that this was an issue. I then had to bring it back for electrical issues as the lights would all start going off in the cab including dome lights and shift buttons. All key fob would not be recognized by the car and would have to be reprogrammed counting 5 times now. Now I am sitting at just oflver 100,000 miles and what I thought was going to be a simple spark plug change gas turned into a complete motor failure. did an oil change and there was no oil in it. The turbo was replaced and now the engine started making a lot of rattling noises and just stopped. …
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. …
*Check engine light on, Reduced Power Light is on, and Vehicle is surging up and down. *Driving on highway and Engine power is reduced, cars behind me honked until I could get over into the right lane because I was losing power. *Yes, confirmed by LaFontaine of Ann Arbor, MI *Yes, inspected by LaFontaine of Ann Arbor MI Customer states check engine light on, reduced power light and the vehicle did have reduced power. Vehicle is surging up and down at an idel. GM assistance, submit for DMA approval to deviate on PET per Scott S DMA. N/C to customer per DMA, If an FSE is needed please submit request. Found air duct not connected to throttle body and throttle body is cause. Inspected and found air duct loose on throttle body. inspected to find throttle body edge is wore and is cause. removed and replaced throttle body to address fail code P0101. …
*Service Transmission message and vehicle goes into neutral. *Vehicle loses power, almost got rear ended by an 18 wheeler when trying to pull over to the shoulder of the highway. *Yes, LaFontaine of Ann Arbor, MI confirmed *Inspected by LaFontaine of Ann Arbor, MI - Cust states the service transmission message light is coming on and the vehicle goes into neutral and stalls, service ll wheel drive message coming on, traction light coming on, customer going about 74 mph and the speedo gauge dropping out, low fuel light coming on even though it has fuel. Per DMA and GM Executive the repairs will be covered 100 %, send DMA pre approval and PET. There is a broken or loose communication wire intermittently disconnecting and causing multiple modules to fault. Could not find broken wire. Request # 9-6483892482 replaced engine harness OP 4069760 ST Time. 8.3 hours Per PET, DMA Pre Auth. …
Headlights flicker when auto stop releases and clicks back on to move the vehicle. This happens when it wants too but usually at the same time service parking brake will pop up, followed by steering is reduced, drive with care.. Lets see what else. Carplay no longer works. No sound. sd card error pops up. Car will not play music through a cord but will via bluetooth, but charges a phone. OnStar light flickering between green and red until I turned off power to the liftgate. (manually clicking over knob to disable) Headlights flickering can cause accidents. Sure hope there's no epileptics out. Yes, orielly. I have documentation, photos, videos, take your pick I'm here to help. Not evaluated at dealer or mechanic, who can afford labor rates? This has been happening for months and I will continue to report till something is done or lives are cared about.
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.
The contact's wife owns a 2019 GMC Terrain. The contact stated that upon making a left turn, the steering wheel would forcefully jerk to right, thrusting the vehicle into the opposite direction. The contact stated that the service ESC and service brake assist warning lights were illuminated. The warning lights would disappear soon after the failure as well as upon restart. The contact had taken the vehicle to the dealer on multiple occasions where he was repeatedly informed that unless the service light was illuminated upon arrival to the dealer, they would be unable to service the vehicle. The vehicle remained in the possession of the dealer and was not repaired. The manufacturer had yet to be notified of the failure. The failure mileage was unknown.
*Check engine light on, engine power is reduced is on, vehicle is surging up and down while in idle, vehicle stalled in service while in park. Charge air cooler tube to the throttle body spring retaining clamp tension weak. Verified charge air cooler tube came off throttle body. Inspected spring retaining clamp. Found spring retaining clamp tension weak. Installed new spring retaining clamp. Charge air cooler tube to throttle body now properly secured *Vehicle power / engine power was reduced while on the highway *Problem has been confirmed by LaFontaine of Ann Arbor, MI *Vehicle was inspected at LaFontaine of Ann Arbor, MI *Engine light came on and the Engine power is reduced message appeared on the dash.
Electrical complaints in other Terrain years
Frequently asked questions
How common are electrical problems on the 2019 GMC Terrain?
NHTSA has 39 complaints about the electrical system of the 2019 GMC Terrain, 21% of the model year's 186 complaints.
Is there a recall for 2019 GMC Terrain electrical problems?
No. NHTSA lists no electrical system recall for the 2019 GMC Terrain, though it has 3 recalls for other components. If the problem is widespread, a repair may still be covered by an extended warranty or a manufacturer service bulletin — ask a dealer.
At what mileage do 2019 GMC Terrain electrical problems start?
Half of the complaints with a recorded mileage happened before about 19,000 miles, and 83% before 25,000 miles.
Is it dangerous?
Owners linked 0 crashes, 1 fire and 2 injuries to electrical system problems on this model year. If you notice symptoms, have the car checked before driving further.
Source: U.S. National Highway Traffic Safety Administration (NHTSA) — owner complaints through October 20, 2026, recalls and defect investigations; fuel economy from the EPA. Complaints are unverified reports and are not proof of a defect. How we rate model years.