2021 GMC SIERRA 1500 Electrical System Problems

Truck went in service 9/17/2025 because the wheels locked up while driving. Transmission was replaced. Picked up truck and 2 hours later the truck shut off while driving and was started back up and was limp mode. Was told wire chaffing and they taped and rerouted wires. Picked truck back up and next day it did the same thing. Took back to the dealer and they said wires again. They taped wires back up and we picked up the truck. We had it 7 days and while driving down the expressway the whole truck shut off and would not start up again. Clearly that is a safety issue. After sitting on the side of the expressway for 10 minutes it started up again and was in limp mode and taken to the dealer again. I don’t know what has been done to it yet as they are not great at...

Muti pro tailgate has electric issues due to moisture. Tailgate will open up driving down the road.

The Intermediate speed sensor 2 and internal transmission harness failed. The repair was to replace the internal transmission harness and intermediate speed sensor. This vehicle is a 2021 and I was told this was recalled on a 2022 only.

experience a automatic OTA update to the info system on my 2021 GMC Sierra(I did not iniciate) which burnt out the radio module which controls the info system. I am being charged $1,300+ for repair due to vehicle being out of warranty(52,000 miles) and no recall on this vehicle model for this issue. GMC does have a recall for this exact issue on the 2021 GMC Tahoe models, but not the GMC Sierra. If the GMC utilizes the same componets for both models of vehicle how doe the recall#N202319250 not cover the exact same issue on both models?

I am an active U.S. Air Force member. My 2021 GMC Sierra 1500 failed GM Recall N252494003 on Sept 29, 2025 (L87 engine loss of propulsion). GM states this defect can cause sudden engine failure and loss of propulsion, increasing crash risk. Despite the confirmed failure, Ocean Cadillac (Miami, FL) told me to keep driving the unsafe vehicle and refused all Courtesy Transportation. The Service Manager admitted in writing that the engine failed, the defect can cause loss of propulsion, and the replacement engine is delayed under GM National Control for up to 3 months — yet they still denied me a loaner or rental. His statements contradict the GM documents he attached: • GM Bulletin DCS7222 says Courtesy Transportation CAN be provided during L87 recall downtime and dealers MUST consider loaners/rentals. • GM FAQ N252494002 says Courtesy Transportation IS available for this recall. • GM FAQ lists recall symptoms...

I took my truck through a car wash and then parked at my parents house. While the vehicle was parked, the trunk latch kept releasing. The trunk popped open. I left it open but you could hear the latch continually releasing and the lights blinking. This went on for an hour and I was unable to drive home because my trunk kept unlatching! A recall was released for other Sierras but not mine. Please investigate my vin and others that may be affected.

I am experiencing a recurring issue with my 2021 GMC Sierra where the dashboard displays a “Shift to Park” warning even though the vehicle is already in Park. This typically occurs when I attempt to shut off the vehicle. The doors unlock as expected, confirming the truck is in Park, but the warning prevents me from turning off the ignition immediately. After a few seconds, the warning usually disappears, allowing me to shut off the truck. This issue is more frequent in cold weather, suggesting a temperature-sensitive electrical or mechanical fault. Based on research and community reports, this appears to be a known issue across multiple GM vehicles, often linked to a faulty micro switch or wiring harness in the shifter assembly. I am concerned about the safety implications, especially if the vehicle fails to shut off properly or if the issue worsens over time. GM has not issued a...

2021 GMC Sierra 1500 [XXX] miles 36,500. My childs seatbelt does not work and the lane keep assist does not work INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

The contact owns a 2021 GMC Sierra 1500. The contact stated that there was an abnormal change with the RPM. There were no warning lights illuminated. The contact received notification of NHTSA Campaign Number: 25V274000 (Engine and Engine Cooling); however, the part to do the recall repair was not yet available. The local dealer was contacted. The dealer received an email from the manufacturer, but the verbiage was incorrect to move forward with the repair. The contact stated that the manufacturer had exceeded a reasonable amount of time for the recall repair. The manufacturer was made aware of the issue. The failure mileage was approximately 39,000. VIN tool confirms parts not available.

GM has has a known issue with a switch/sensor placed at the base of the shifter that causes the “shift to park” error message that prevents the electrical system from shutting down when the vehicle is physically in park and the engine is turned off, In fact, GM has issued a recall for several different models in which a “shift to park” error message is displayed because of the poor design; however, they continue to see the same issue occur but claim it is not a warranty issue (unless it occurs within 3 year/36,000 mile time frame. This is not an issue that can be caused by owner misuse, and I believe that GM should be held liable for repairs given that the issue is, and has been, known for several years now.

While driving my truck with my wife and two young boys, the truck engine completely shut off while operating it. We were stuck in the middle of the road and had to cautiously wait until we could move the vehicle out of the way. The engine locked up. Now they are trying to repair the engine with the same exact engine that is on recall and potentially put me and my family in the same dangerous position.

See attached vehicle repair orders/Carfax/vehicle registration. The trucks transmission has been slipping/jerking hard since I pulled off the lot at dealer ship. Its burning oil no leaks has been doing so since the day I drove off the lot at dealership. I have asked to fix or address and problem still exist. They sold vehicle as everything was working The Left head light wasn’t working the day I drove off the lot didn’t notice until I got home I reached back out to dealer to explain and said light had a short in kept truck for almost a week said the were going to replace the head light and never did. The remote start wasn’t working the same day i purchased the truck but sold it as everything is working. I went to try it as I was getting ready to leave dealership and did nothing. Then I discovered the...

Transmission recall was performed at a gmc dealership. Vehicle has been the the shop repeatedly since. Coolant control valve crank case position sensor new catalytic converter and dpf system. New low temp coolant loop pump. In the shop now for another low temp coolant pump that’s been shorted out. Seems to have on going electrical issues since recall was performed

ESC ERROR PARKING BREAK NOT RELEASING Dashboard lights started flashing Check engine light came on

This truck, along with many others, has had wiring harness issues. My truck has fought this issue within the first six months of owning the truck. Since Jan 2025 it has left me stranded 3 times to be towed, and in the shop a total of 6 times for wiring harness issues. Rubbing that GM is 100% aware of how its designed. This has caused the truck to hesitate, shake, lunge, go in and out of gear severely hard then shut off while driving. All three time this happened to me recently i was on the interstate. GM has work orders out with all the codes and symptoms but wont do anything about it. Yes, i am out of warranty, but i am now paying over $5,000 for a new harness to be installed by a different dealer. The dealer that had always worked on this truck requested $8,100 so...

The contact owns a 2021 GMC Sierra 1500. The contact stated while the vehicle was parked, the contact attempted to turn off the vehicle; however, the vehicle remained running. A message was displayed to shift to park(P). The contact stated that the lights, radio, and other functions remained operational. On another occasion, the vehicle jerked, and the steering was difficult to turn. The dealer was contacted; however, the vehicle had not been taken to be diagnosed or repaired. The contact also stated that the trunk failed to fully close. The message that the trunk was open was displayed. The contact attempted to close the trunk and message on the displayed was turned off; however, the trunk remained slightly open. The vehicle was not taken to be diagnosed or repaired. The manufacturer was not made aware of the failure. The failure mileage was approximately 63,315.

My truck was part of a GM buyback program where GM Corporation bought the truck back to fix it around Aug 7th 2023 for engine problems. I am reporting this because I do not believe that GM ever reported this to NTSHA. There are also other issues happening at the same time period that should be looked into that may or may not be coincidences. At or before 10,126 miles the truck started having engine lifter and other engine issues. General Motors will not tell me exactly what was done other than lifters according to paperwork supplied. It may have had other issues like a spun bearing but it was never disclosed. Can NTSHA please look into this and information is found, could I please get the records. I asked for the paperwork of what was done while GM owned and troubleshot all the problems. I was told that information...

Multi functional tail gate will open on its own while driving. I have had this repaired by gm 3 times and still have issues. This problem is currently on the recall list for 2500 hd series trucks and the 1500 series trucks in Canada but not on recall in united states. This problem poses a life threatening problem while on the road due to contents of truck possible becoming projectiles to other drivers due to tailgate opening on its own .

[XXX], I PURCHASED A 2021 GMC SIERRA 1500 FROM FAULKNER CHEVROLET IN BETHLEHEM, PA. I TEST DROVE THE VEHICLE BEFORE PURCHASE AND IT SHOWED NO INDICATION OF ANY MECHANICAL ISSUES THAT I WAS ABLE TO DETECT. I WAS SHOWN BY THE DEALERSHIP THE CARFAX AND WAS INFORMED THAT THERE ARE CURRENTLY NO RECALLS FOR THE VEHICLE. I WAS LED TO BELIEVE THAT THE VEHICLE WAS IN GOOD CONDITION AND SAFE TO DRIVE AND, THEREFORE, AGREED TO PURCHASE THE VEHICLE FOR THE AFOREMENTIONED PRICE (INCLUDING TAX AND TITLE FEES). I PURCHASED THE VEHICLE WITH 60,077 MILES ON IT, AND AFTER DRIVING IT NORMALLY FOR ONLY 5 DAYS (ON [XXX]) IT BROKE DOWN AND I WAS STRANDED ON THE HIGHWAY 16 HOURS FROM HOME. I WAS ABLE TO GET THE VEHICLE TOWED AND PAID $1,200 FOR THE STARTER TO BE REPLACED, WHICH IS WHAT THE MECHANIC SUGGESTED BUT THIS ENDED UP BEING...

The contact owns a 2021 GMC Sierra 1500. The contact stated while driving at an undisclosed speed, the transmission slammed into gear and the rear wheels locked up. In addition, the vehicle decelerated independently. The vehicle was driven to the shoulder of the road and turned off. The vehicle was restarted, and the contact noticed that the vehicle was independently reset. The vehicle was taken to the dealer where it was diagnosed with a failed wiring harness. The contact was informed that the wiring harness needed to be replaced. The vehicle was not repaired. The manufacturer was made aware of the failure and a case was filed. The contact was advised to contact the NHTSA Hotline and report the failure. The failure mileage was approximately 60,129.

Assure Guard (877-831-3077) Contract number [XXX] GMC Customer Care Melissa (866-790-5600 Ext [XXX] ) Case#[XXX] Dealership: Phil Moore GMC (601-956-0150) My truck is barely 4 years old. I should not have this problem . Why is it no one guarantee the product they make? I paid too much money for this vehicle financing it as a new truck. I paid 766.95 to replace/install the shark fan antenna on the roof of my truck because it literally came loose on his own. No one (dealership, GMC, Assure Guard) would assist with repairs. The shark fin antenna started leaking water and it was wobbly where, it was no longer sealed on the body of the truck. Water leaking through out the ceiling/roof. I didn’t do anything to cause this! GMC Customer Care refused to refund nor, help with the cost of repair. I tried to file a claim with my extended warranty...

my truck keeps having this same issue since [XXX], always take it to team Gillman second august 26 same reason they replaced the battery but is a manufacturing defect while i am driving stops out of sudden AND THIS IS THE THIRD TIME THEY SUPPOSED TO CALL ME I HAVENT RECEIVE NO CALL IS AT TEAM GILLMAN SAME REASON ONLY HAS 18000 MILES MY NAME IS [XXX] CELL [XXX] INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

The contact owns a 2021 GMC Sierra 1500. The contact stated while driving at various speeds, the tailgate opened unintendedly. No warning light was illuminated. The vehicle was taken to the dealer but was not diagnosed or repaired. The dealer informed the contact that the VIN was not included in GM Campaign Number: N232426401. The manufacturer was not notified of the failure. The failure mileage was approximately 57,000.

When accelerating and shifting into drive, the vehicle is experiencing a lag when moving forward. The rear wheels are not latching into the designated gear. When vehicle comes to a complete stop, it will not accelerate and does not want to move. The problem has been reported and there are multiple recalls on similar vehicles of the same make and model. There were no warning symbols or notifications generated at the time of inspection.

The electronic tailgate switch is malfunctioning and opening on own. We brought in and paid 2 times to have repaired and now the third time has happened. It’s appears this model is recalled in Canada but not US. Why is that when it’s the same parts used and the HD models have also been recalled. Why is our truck not recalled for this?

My vehicle was issued an OTA ( over the air update ) automatically, and the update failed, leaving the screen in my vehicle inoperable, with a message displayed stating " Update failed return to dealer" My vehicles radio/information system is now inoperable. The blue-tooth calling capability is also inoperable. This is a safety issue due to the fact that I am a resident of Minnesota and we have a law that states it is illegal to use your phone while driving. In addition, I am unable to receive severe weather alerts via the radio and do not have the ability to make phone calls in my vehicle in the event of an emergency since it is illegal to use my phone in MN while driving. This is a serious safety hazard The GMC dealer (Mills GMC in Baxter, MN ) that the vehicle is currently at has stated this is...

Radio screen will go blank randomly after turning the truck off the I can here the radio but can not see any screen. After turning the radio of an exiting the truck radio still plays all of the sudden the radio will go off and restarting the truck radio is working again .At any random time the radio will go blank again

The inner tailgate continually releases the upper tailgate, which then opens when the vehicle is driven. When latched, the tailgate immediately opens again. This is reproducible. I gather the switch is shorted closed, leading to the release of the tailgate. This poses a risk to items in the bed of the truck leaving the vehicle unexpectedly while in motion. The truck has not been to the dealer yet, there has been no inspection of the vehicle by any authority. The vehicle displays a warning “inner tailgate open.”

The component that has failed is the engine coolant flow control valve AC Delco part number 55516369. Unfortunately the part is still installed on the vehicle. It has been taken to a dealer and this is a known issue but no recall has been issued. The check engine comes on sometimes but not always, sometimes the pickup has plenty of power to drive and sometime it will barely pull itself, all in the same trip without shutting the ignition off. The symptoms first started in December of 2023, but were sporadic, now it is nearly everytime the pickup is started. It is extremely dangerous to drive this vehicle when it has a problem. You cannot tell if it will accelerate normally or is you will push the pedal and it does nothing. The part to repair the problem is on backorder and no release date is yet available. We have...

Tail gate failing from water intrusion. Wont stay up while driving. Already a recall for it in Canada but nothing in the USA where i see others have the same problem

Tailgate drops without warning, lower button on tailgate doesn't work.

It started year and a half ago involving my tailgate. The buttons to operate by upper and lower tailgate failed to operate on the rear of the truck, but cab button and remote button would open the full tailgate. Returned truck to dealer and they replaced the rear control. It worked for approximate 4 or 5 months the the total tailgate button failed, half tailgate button worked no problem. About 6 mths ago I went to drive to work and hit a bump felt like something bounced but really didn't think of tailgate being open. Drove on interstate for 7 miles at speed of 70 to 75 mph. I had my structural firefighting equip in the bed. Stopped at a drive thru for coffee then drove 5 miles to other side of town to my workplace put truck in reverse and my camera showed the ground, my tailgate was open....

While driving down the road at random times of the day, random days, random drive periods, random locations, the DIC and touch screen along with radio will shutdown and restart, like rebooting the system or just starting the truck. I loose the mph, gauges, navigation, everything on the dash and touch screen the it will come back on like nothing happened. I have contacted 2 dealers and they say I need to download updates but when I go to update it is not required or needed.

My 2021 GMC 1/2 Serria SLT 4x4 Crew Cab short bed, V-8 Gas engine with Automatic Transmission. I bought this pickup used with apprx. 41k miles on it. I had it about 2 months when I went out to start it and the battery was completely discharged, it would not even click or any lights come on. I hooked it up to a battery charger and got it started, took it to a shop and had the battery and alternator check which both were ok. Drove back home and went out the next morning and the battery was completely drained again, got it started and went an put in a new battery. 16 days later it did the same thing this time it smelled like wires burning when I opened the hood. Called the dealer I bought it from and they put it on a diagnostic machine for over 3...

Tailgate opens when driving and when parked. I thought something must of hit the button on the dash the first time it happened but now it is constantly doing it on its own. It has damaged the hitch.

My son got into the car to drive it and saw a black screen with a message that states “update failed, see dealer” and had multiple languages. Since that date, he has no GPS or backup cam, which he relies on as a new driver. Nothing at all in the info system works.

While towing a new 2023 Airstream trailer on Interstate route 95 in New Hampshire my GMC Sierra truck driver display flashes a " check Trailer wiring" error message. When this message appears all brake function to trailer is lost makeing driving unsafe. The connection sometimes can intermittently and continuously reconnect momentarily and brakes reengage for seconds until they disengage again with repeated "check Trailer wiring" error message . Sometimes the brakes just disengage end never reconnect until error codes is cleared by GMC dealership. It's extremely unsafe to pull off exit and have trailer brakes reengage because they jam with high gain because vehicle brakes need to be applied very hard to over compensate for "NO" trailer brakes. GMC dealership has identified certain error codes with their computer but NO suggested fix!

Less than 5 minutes after my husband and 2 children parked the car and came inside, a neighbor walking rang our doorbell to let us know there was something on fire in our driveway. We ran to the back to find his truck engulfed in flames coming from the engine. We quickly called 911 and exited the house/property. The truck continued to burn with 20-25 foot flames and very black smoke for about 40 minutes until the fire department was able to control the fire. The fire was hot enough that the entire engine was significantly burnt, the seats and steering wheel were gone, the glass shattered and melted, and the tires exploded and melted. Thankfully, everyone was out of harms way and safe through this incident. However, it has been extremely traumatic on my family and neighbors and has taken a lot of time and energy to try to...

The contact owns a 2021 GMC Sierra 1500. The contact stated while driving at various speeds with the ONSTAR/GPS, turn-by-turn driving directions activated, there was an unknown notification flashing on the instrument panel and radio. The speedometer was obstructed and failed to work as needed. The screen sporadically went blank. While depressing the dismiss button on the steering wheel, the button failed to correct the failure. There were no warning lights illuminated. The vehicle was taken to the local dealer and the system was rebooted; however, the failure recurred. The vehicle was taken back to the local dealer and the contact was informed to turn off the vehicle, open the door, and then restart the vehicle to reboot the vehicle. The vehicle was taken to another local dealer, Bill Cramer Chevrolet Buick GMC (2251 W 23rd St, Panama City, FL 32405) but the vehicle was not diagnosed or repaired. The...

My truck’s battery is dead after sitting for a few days. There is a manufacturing deficit causing parasitic draw. This is a safety issue because it leaves us stranded after parking the vehicle for a few days. The General Motors dealership refuses to do it anything about it. They claim it’s normal.

The contact owns a 2021 GMC Sierra 1500. The contact stated that while operating the vehicle, the dashboard gauges, instrument cluster, and infotainment center malfunctioned and became inoperable. Additionally, while starting the vehicle, there was a loud cranking sound coming from the engine compartment and the vehicle would not immediately start. The vehicle was taken to the local dealer, but the cause of the failure was not yet determined. The manufacturer was notified of the failure, but no assistance was offered. The failure mileage was 100.

The contact owns a 2021 GMC Sierra 1500. The contact stated while using the GPS, the digital speedometer failed to operate as needed. The contact notified the dealer of the failure and the system was rebooted; however, the failure persisted. The manufacturer was made aware of the failure and a case was opened. The approximate failure mileage was 1,000.

While driving, when approaching speed of 40 mph, the engine begins to have dull shutter intermittently as though I am going over pot holes or rumble strips when I am not. Regardless of time or day or weather the truck has performed in this way. I have had it to the dealership twice for the issue. The first time they said they didn’t feel anything and unable to duplicate the problem. The second time, the vehicle was with the dealer for several days trying to determine the other issue it was there for. I requested they again try to recreate the concern. The service assistance asked if I was willing to ride with the technician to see if I could point it out for him. In scheduled a time to do so, when I arrived, the technician was not there. I reside an hour away from the dealership. Making these...

The console radio dash has gone completely black while both driving and while using it for the speaker/phone system. The incident resulted in the entire system restarting.

Can turn vehicle off while in gear (drive specifically). When you let off the brake, the truck acts as if it is in neutral. Discovered in my driveway when accidentally forgot to shift into park when I pulled in and pushed the stop button. Truck turned off, which would only expect if in park (or neutral), let off brake, and it began quickly rolling backwards as if it was in neutral. Fortunately the brakes were working, but had any children been riding a bike on the sidewalk or walking by, my truck may have hit them. Had I been more distracted and not noticed initially, it could have rolled into the road and hit my neighbors truck. This behavior can be reproduced every single time, and I can easily supply video.

Less than 300 miles on the vehicle and it has thrown an error code P2B60. Relating to the engine coolant flow control valve position sensor. I have taken it to my local GM service center and they cannot see me for weeks. As of this morning the check engine light has disappeared but my fuel economy has severely decreased. It seems suspicious and possibly dangerous that it showed a check engine light with a warning of reduction in engine power the night before and disappeared in the AM

Started vehicle up in public parking lot and it had service power steering and ESC messages. Vehicle could not turn and had to be towed to dealership. The problem has been confirmed by the dealer but they have had the vehicle for 2 days and cannot fix the problem. Dealer states code keeps coming up in BCM but they are not sure why or how to confidently fix it. There were not warnings or any symptoms of this problem as it drove to work fine that same morning.

Prior to this incident I had lifter failure on my 2021GMC SierraAt 8464 miles, I was on my way to work and I heard a loud bang and I had to pullover off the highway, my dad had to come all the way out To get the vehicle because it had major engine damage and it was on a holiday so no one would come help me.The vehicle was in the shop for over a week getting these repairs done, upon receiving vehicle it had been a week and I received service four-wheel-drive messages on the dash.Trying to use four-wheel-drive after this was a no-go every time I push the button nothing would happen it would stay in two wheel drive.After this I made an appointment with the dealership for this issue to be fixed, as I was going to get readyTo leave again with the truck having no issues...

I started my truck this morning, drove it 3 miles, and all of a sudden got an ESC warning, Parking break warning, and a degraded power steering warning all at one time. My steering wheel started vibrating vigorously, a clanking sound started under the hood somewhere, and none of my safety features worked after.. Cruise Control, Vehicle Collision Control, Vehicle Gap sensors, etc.. The vehicle is currently at the dealer being looked at.

This is the second time I stop at the grocery store for about 15 or 20 min, get back in the car push the start, then the truck keep cranking with no start for about 20 seconds. Then I try second time and it fires up.