2020 GMC Sierra 1500 Electrical System

Power Steering works sometimes and then stops Trailer Break system issues

Had GMC (Leominster, MA), perform the safety recall for the transmission on my Sierra. This is the one for the rear wheel lockup that requires a software update. My battery was completely dead after the vehicle sat for a week. No accessori s plugged in, and it's a 6 month old battery Battery tested fine and is charging now, but it appears the CPU never fully powered down after the software update, resulting in needing multiple jump starts and 3+ hours of run time to charge the battery enough to turn over on its own. I can see this being a safety issue in relation to the Auto-start, because when it is being used, the battery is needed to restart the engine. This could result in a stall at an intersection, and if drivers are not alert, may collide with a stalled vehicle.

While driving my vehicle it began down shifting harder than normal (at various speeds and road (highway, city and dirt road)); along with a noticeable burning smell after every trip. GM Maintenance personnel discovered that the wire was chafed and arching / catching on fire underneath passenger side resulting in the burning smell and the wiring issue aligned to the transmission. Personnel took a video and provided to me as evidence of the fire / smell; however, that was on their official GM app so i was unable to download

After repair got a few miles down the road and noticed the volt meter jumping back and forth between the white lines. Line would slowly go up to max line and then slowly drop back down to lower limit and continue to go back and forth. This was very concerning to myself and i was waiting for something to fail while driving. Got about 10 miles away and was to concerned / returned the vehicle Informed by GM Maintenance tech that this is what / how the vehicle is designed and that it is the operating within its parameters. I expressed that only time i noticed something like this was prior to an engine light / electrical failure; however, maintenance team expressed GMs stance that it is operating within tolerance.

While driving on interstate transmission would “lock up” momentarily creating drastic drop in speed and unable to shift gears and accelerate. “D” would start flashing in dash board. Dealership said this is unrelated to current recall about rear wheels locking up from valve body failure and instead this is an electrical issue. Dealership also stated this is the 2nd truck in a week they have had come in with this issue. Almost caused accident on interstate with my family and I as a result of sudden drop in speed and unable to accelerate with multiple cars behind us.

We are unsure what happened that caused the issue. One day the dashboard just started giving us error messages, 3 of them to be specific. One says check turn signals, another says check trailer brake light and another something else about brakes or turn signals. (We have to dismiss them all before anything on the dash is viewable). This issue is causing the blinkers to blink fast as though the blinker lights need replaced and it happens when turning right or left. The alerts continue to give us error messages every few minutes, even after we have dismissed them all. We had the truck at a shop trying to figure out the issue and his guys spent hours and replaced things he thought were causing the issue but nothing fixed it. He referred us to take it to the dealership service shop for troubleshooting so we took it to the GMC dealer where we bought the truck. GMC has already spent hours, maybe 5-7 hours at $150 per hour, trying to figure out what's wrong and have been unable to find anything wrong. The truck is still at the GMC dealership shop but I can get pictures of the errors when we get it back.

[XXX] INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6). *TR

Service ESC, Service Power Steering, antilock brakes disabled all flashed on information center of vehicle. Service engine light, antilock brake light, ESC, low battery all illuminated. Vehicle would not start - try to start it would go through all issues on information center. This is the same ESC issue described for 2019 Silverado and GMC Sierras.

Bought 9-4-2020. On 9-4-2021 went start vehicle and no electrical power, battery dead. Will not hold charge to start. Brand new purchased at Morgan GMC in Shreveport Louisiana

The display for the backup camera and infotainment system became blank. Other owners have the same complaint. This is a serious safety issue because I was backing up when it went blank.

TL* THE CONTACT OWNS A 2020 GMC SIERRA 1500. THE CONTACT STATED WHILE DRIVING, THE SIDE VIEW MIRROR'S BLIND SPOT ALERTS ON BOTH SIDES ENGAGED WITH NO VEHICLE NEARBY. THE VEHICLE WAS TAKEN TO TURNER BUICK GMC (612 E MAIN ST, NEW HOLLAND, PA 17557) WHERE THE CONTACT WAS INFORMED THAT THE SENSORS WERE DIRTY. THE CONTACT THEN WASHED THE VEHICLE HOWEVER, THE FAILURE RECURRED. THE VEHICLE WAS NOT REPAIRED. THE MANUFACTURER HAD NOT BEEN INFORMED OF THE FAILURE. THE FAILURE MILEAGE WAS APPROXIMATELY 400. THE VIN WAS NOT AVAILABLE. *BF

DISPLAY IS DANGEROUSLY TOO BRIGHT WHEN BACKING UP CANNOT SEE TO BACK UP VEHICLE SAFELY

VEHICLE DOES NOT START AND FLASHING VARIOUS CODES SERVICE JUST ABOUT EVERYTHING ON THE VEHICLE

BATTERY WAS DEAD IN THE GARAGE. CALLED ROAD SIDE ASSISTANCE WHO JUMP-STARTED CAR. CAR WOULD NOT GO INTO GEAR. WE ROLLED IT OUT INTO DRIVEWAY WHERE IT SAT FOR 24 HOURS. WHEN IT WAS LOADED FOR TRAVEL TO DEALERSHIP, IT CRANKED AND WAS DRIVEN UP ON WRECKER TRAILER LIKE IT HAD NO APPARENT PROBLEMS. WAS CARRIED TO DEALERSHIP WHERE THEY RECHARGED AND CHECKED THE BATTERY AND RESET 14 DIFFERENT CODES WHICH WERE LOST WITH THE LOW VOLTAGE.

BRAND NEW TRUCK PURCHASED IN MAY 2020. VEHICLE WOULD NOT START ON 7/2/2020 AND A NEW BATTERY WAS PLACED IN THE VEHICLE. THE TRUCK WOULD NOT START AGAIN ON 7/17/2020 UNKNOWN REASONS...

REVIEW CAMERA IS EXTREMELY BRIGHT WHEN BACKING. IT'S SO BRIGHT THAT A GLARE IS THROWN ONTO REAR WINDOW MAKING IT NEXT TO IMPOSSIBLE TO SEE OUT REAR WINDOW OR USE SIDE VIEW MIRRORS. I OFTEN REVERT TO TO OPEN DRIVERS DOOR AND LOOKING BACKWARDS THAT WAY. SOMEONE IS GOING TO GET RUN OVER AS YOU CANNOT SEE WHERE YOU ARE BACKING. VERY DANGEROUS!

THE NIGHT TIME BACKUP CAMERA IS REALLY BRIGHT AND BLURRY AND IT MAKES IT HARD TO SEE WHEN BACKING AT NIGHT