10.0

really awful
Crashes / Fires:
1 / 1
Injuries / Deaths:
0 / 0
Average Mileage:
9,984 miles

About These NHTSA Complaints:

This data is from the NHTSA — the US gov't agency tasked with vehicle safety. Complaints are spread across multiple & redundant categories, & are not organized by problem.

So how do you find out what problems are occurring? For this NHTSA complaint data, the only way is to read through the comments below. Any duplicates or errors? It's not us.

2018 GMC Terrain electrical problems

electrical problem

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2018 GMC Terrain Owner Comments (Page 1 of 2)

problem #29

Apr 262024

Terrain

  • miles

A D V E R T I S E M E N T S

Safety was put at risk when brakes went out without warning, and unable to use emergency brake at that time. Car was serviced for over $1700, with the mechanics stating that the piece -??blew up.-??

- Olathe, KS, USA

problem #28

Jan 012024

Terrain

  • miles
Rear side windows in hatch area leaked filled up spare tire compartment with about 3-4 gallons of water. Now navigation doesn't want to work, sunroof not working, electric systems are not working right

- Willits, CA, USA

problem #27

Dec 202023

Terrain

  • miles
The door locks began to have issues; the locks started to work only occassionally for no apparent reason. I've been locked out of the car several times and had to use the auxiliary key. Plus I couldn't lock the car while I was inside as the interior door lock button wouldn't lock or unlock the doors either. It's not a kefob or battery issue and no lights on the dashboard. The dealer reports that they couldn't reproduce the issue. However they found corrision on the electrical harness inside the passenger front door. I replaced an electrical harness in the rear bumper 18 months prior for corrision found. The dealer says they received a service bulletin on the "electrical harness" issue however the dealer won't cover the cost of $500 to replace the harness. As this deals with the electrical system, my concern is that it may effect the operation of other components of the car while it's running. Safety and security is of the utmost importance whether at home or away as it regards to being able to lock or unlock the doors.

- Columbus , OH, USA

problem #26

Dec 062023

Terrain

  • miles

A D V E R T I S E M E N T S

On Wed., Dec. 6 around 3:15 pm during heavy traffic on FWY [XXX], cars slowed down to a brief complete stop. When I went to start slowly as traffic began to move, engine completely shut down. I could not open windows or my door to get out of vehicle. Immediately called 911 and was transferred to DPS. It took approximately 65 minutes before I had help and was finally towed from the dangerous freeway lane where I was stuck and with vehicle completely stalled and locked down, I couldn't even get car in N to be able to have help moving to a non dangerous place outside of the FWY lanes. This is the fifth time this car locks down. I've learned to open a panel by the foot brake area, pull a lever in that area and be able to move the car to a safe location until I got towed into the dealer. It is the second time that this has happened in a potentially dangerous street and now Freeway. Danger to myself and many others that had to maneuver around me. The first time (around 2020) the car totally shut down, it was reported that a computer harness had to be replaced. This last time I was faced with such a dangerous situation on a FWY it was determined that the ECM (Engine Control Module) had caused the shutdown and locked the vehicle to where I could not even get out for close to an hour. The ECM was replaced by GM and the car is running again, but my shock and trauma still haunt me as to the self and others danger that was present.. GMC Dealer finally determined after several attempts that ECM was the problem. Unsure if available to inspect it. Delivered car back 12/8.. Heavy freeway traffic at peak hour put me and many others in serious danger.. My dealer report reads it was difficult to diagnose and finally find ECM was the problem..Vehicle has not been inspected by Manufacturer, police, or insurance..A few minutes before this lock-down an engine icon appeared while on the FWY. Previous shutdown incidents had no warnings or messages before locking up. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFO

- Glendale, AZ, USA

problem #25

Oct 112022

Terrain

  • miles
There is an has been an issue with my electrical system says I purchased this car in 2017. Myself believe that the issues have not been documented until 2020. When my racy begins to run out, my engine light has been coming on and I-??ve been getting the same code P1101 I took my vehicle to GMC and they told me that the engine light came on because the tape came loose. I brought this vehicle and there-??s no way there should be no tape on it. The service tech also told me that if the problem continue to bring it back and I will have to pay $120 or whatever the label rate was for them to research I contacted GMC to file a complaint and I received the whole bunch of calls from a guy named Kevin. I believe he told me that he had been contacting [XXX] and no one returned his call and that he was sorry he couldn-??t help me. This is my report number one of them from GMC. [XXX]. Everywhere I take my car they tell me that they have a lot of customers with the same issue and they tried to replace what the code is matching which is the mass airflow sensor but that does not help there is some type of problem with the engine or the electrical system with this vehicle. I am not the only consumer that has had this problem. I don-??t know what to do. I have two kids I cannot afford to keep pay and label rate for them not to find the problem. I am also attaching the typical email that GMC sent out when they are working with the dealerships because I have been in contact with them and the person that was calling and then they sent me this email. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

- Chicago, IL, USA

problem #24

Nov 272022

Terrain

  • miles
Temperature sensor for the engine went out...which now affects my remote start not to work

- New London, WI, USA

problem #23

Jun 132022

Terrain

  • miles

A D V E R T I S E M E N T S

Radio, hands free calling, and light on mirror shorting out. None of them work. It-??s like it has a short in the wiring.

- Henagar , AL, USA

problem #22

Apr 012022

Terrain

  • miles
1. 2018 Terrain would not start in a parking lot. Remote was used after several attempts to start with push button failed, and after a slight hesitation, engine started. Vehicle was driven about 6 miles without incident. 2. Vehicle was driven about 10 miles the next day and start/stop engaged at a stop light but would not restart. After about 3 minutes of cycling throught the starting procedure, the vehicle started. Drove another 8 miles without incident. 3. Next morning, drove about 3 miles to intersection where start/stop engaged but would not restart. After about 30 minutes of cycling through starting procedure and an attempt to jump start was made the vehicle restarted. At this point, the vehicle was taken to Romain GMC for service. A new battery was installed and other related operations.After about 10-15 miles, the vehicle would not start. Remote was attempted but it would not start. After about an hour, vehicle started and was driven back to Romain avoiding the stop/ start engagement.

- Evansville, IN, USA

problem #21

Oct 282021

Terrain

  • miles
Multiple warning lights are appearing at once (Automatic brake assist, forward collision assist, parking brake released) When the car is put in reverse, the radio turns off for a brief moment and the steering assist warning shows on the dash. The steering wheel snatches back in the opposite direction causing a safety concern. The car also completely cuts off after the auto-stop takes effect at red lights causing me to have to pump the brakes at least twice to re-ignite and be able to accelerate.

- Upper Marlboro, MD, USA

problem #20

May 312021

Terrain

  • miles
The "Service Brake Assist" issue in other 2018 GMC SUVs is happening in the 2018 GMC Terrain, but it is not part of the recall. Our brakes became EXTREMELY difficult to press right as we were turning onto the on ramp of an expressway. Thankfully we were smart enough to pull over and not get on the highway. Had we done so, I may not have been here to type this complaint. The brakes be come extremely difficult to press and that message shows. Dealership is going to charge me $400 to replace a vacuum pump - they were not interested in the information I have around this issue in other GMC SUVs since it isn't a formal recall on the Terrain. I could have died yesterday due to this braking issue. I've owned this car for 3 months.

- Redford, MI, USA

problem #19

Feb 232021

Terrain

  • 34,000 miles

A D V E R T I S E M E N T S

When restarting after vehicle "auto stop" I am getting "service brake assist" and occasionally "service ESC" warnings. These warnings were associated with brake failure in GM SUV's and pickups and were subject to a recall. No such recall exists for the Terrain. I haven't yet experienced a brake failure but GM seems to want to wait until I do to fix the problem.

- Chillicothe, OH, USA

problem #18

Dec 312020

Terrain

  • 55,200 miles
The service stabilitrak light continues to come on. When it does, almost all of the lights on the dash light up and the car puts itself in neutral and shuts off. This has happened 5 times in the past two weeks. Twice with my [xxx] in the car. Parts of this document have been redacted to protect personally identifiable information pursuant to the Freedom Of Information Act (FOIA), 5 U.S.C. 552(B)(6). The car was purchased 12/23/2020 and it first shut off with the service stabilitrak warning 12/31/2020. I've taken it to the dealership for repair. They replaced the front right wheel sensor today and immediately after leaving their lot, it shut off twice. I did a search on the VIN and found that this vehicle had issues at 11K miles and 27K miles. Now again at 55K miles. The car just shuts itself off while driving. First time it happened, I was rounding a corner in high traffic and in mid turn, the car shut off. I was almost hit by several cars. This vehicle is dangerous. It happened once while on the highway with my 15 month old in the car and today it happened twice with her in the car.

- Decatur, GA, USA

problem #17

May 012020

Terrain

  • 52,000 miles
Car shuts off completely at a stop and no power at all untill it is jump started.

- Brownsville, TX, USA

problem #16

Sep 012020

Terrain

  • 39,600 miles
My 2018 GMC Terrain has major issues that almost caused me to hit a wall on the expressway due to a brake assist issue that other owners have a issue with and GMC has done nothing to help the buyers, where can we the buyers get help with issues GMC is well aware of??

- Park Forest, IL, USA

problem #15

Jul 062019

Terrain

  • 15,615 miles
Radio plays random radio stations and will not allow radio to be turned off when vehicle is turned off ( no power to the vehicle, doors are opened and the fob is over 500 ft away). Radio screen flashes to a blank screen. Does not read contact information for cellphone connected to vehicle. Will not allow phone calls to be made and will continue to play music through radio and car speakers while phone is engaged in a telephone call ( once call is able to be placed). Android auto feature stopped working. Vehicle will slip out of gear and randomly put self into an overdrive. Vehicle will not accelerate despite gas petal being almost to the floor and then will jump rapidly and accelerate quickly. Vehicle smells like rubber is burning under the hood at various times.

- Jacksonville, NC, USA

problem #14

Oct 012019

Terrain

  • miles
Recall on the engine block heater. The dealership is unable to get the part to replace. I took in over 6 months ago and still have nothing.

- Farmington, CT, USA

problem #13

Oct 172019

Terrain

  • miles
My car just completely shut down out of nowhere. It has happened twice when I was slowing for traffic and when I was in a parking lot. The first time I couldn't get out of the car because the door wouldn't unlock. Then the power came on but the car would not turn over. It has push button gear shifts and would not go into neutral. I had to call the police to assist until the car was towed because I was on a very busy and dangerous street. I honestly was scared someone was going to slam into me. The second time I was looking for a parking spot and it stopped. Luckily I always keep the doors unlocked since first incident had to be towed both times. As of today it is still at the dealer trying to be fixed for a second time. They 'thought' they fixed it the first time but it happened again. The dealer has had my car since October 17. They claim they know what it is. They replace some engine module and are now waiting on a push button for the gear shift.

- Carmel, IN, USA

problem #12

Jul 122019

Terrain

  • 27,000 miles
Screen went black and warning chimes and seat vibration did not go off when backing up. Had to file a claim with insurance to fix my dented bumper. I also experience issues with the audio buttons on the steering wheel. I am not able to change the song in I am on apple play and there is always a delay when changing radio stations.

- Webster, TX, USA

problem #11

Sep 092019

Terrain

  • 30,000 miles
The screen on the dash which includes the radio and back up camera goes white at random times and does not work. I have had the radio/screen replaced and it still does it. I have had many updates with the screen.

- Yulee, FL, USA

problem #10

Aug 202018

Terrain

  • 10 miles
Wiring harness not weather sealed N shorted out after dealer washed car on delivery

- Powell, OH, USA

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