84 of the
769 complaints filed about the GMC Sierra 3500
are about the electrical system —
11% of everything owners reported.
The worst model year for it is 2024.
The contact owns a 2019 GMC Sierra 3500. The contact stated that while attempting to switch lanes, the side-view cameras failed to operate as needed. The vehicle was taken to a dealer where it was diagnosed with a disconnected wire from the side-view cameras. The wire had poor connection, which caused the cameras to fail due to low voltage. The vehicle was not repaired. The manufacturer was notified of the failure and stated that the part to repair the vehicle was no longer manufactured. The failure mileage was 53,004. The VIN was unavailable.
NHTSA complaint #11753630 — an unverified report by a vehicle owner.
"The integrated trailer brake system abruptly fails while towing heavy loads, completely disabling trailer break stopping power and creating an imminent threat of highway crash and serious bodily injury." The sound system inherently stops working and will not produce sound from any device in the truck weather that be Hazards, Blinkers, Radio including AM,FM, Sirus Radio, Bluetooth or Car play as well as OnStar. The truck has been taken to a certified GMC dealer 4 times for these exact issues with also being provided the service bulletin information #N232414840 dated July 16, 2025 stating that the 2024 gmc 2500/3500 HD trucks requiring a new Trailer Break Control Module. This issue has been on going from September 2025 and still an issue as July 16, 2026 and still in the Shop today with a call back stating ready for pick up with the same module but dealer stated re flashed module. ( this is the 3rd reflash )
NHTSA complaint #11750810 — an unverified report by a vehicle owner.
Have been driving it on four separate occasions and the engine will start running rough and shut off leaving me with no power brakes or power steering. Once when I was going about 30 miles an hour the other three times when I was coming to a stop with a trailer on just took it in Kendall Chevrolet for the first time they are still working on it but unable to duplicate the problem this is a very serious safety concern for myself and possibly for others that have the same issue
NHTSA complaint #11744605 — an unverified report by a vehicle owner.
Randomly when the truck is turned on, the turn signals will stop working, no noise, nothing. When this happens, the infotainment system also stops working. It is unsafe to be driving and not knowing if your signals are working or not. This has been happening since the truck was purchased from the dealer.
NHTSA complaint #11722798 — an unverified report by a vehicle owner.
This 2024 GMC Sierra Heavy Duty has experienced a continuous pattern of major mechanical and electrical failures since early ownership. The vehicle required a complete engine replacement under warranty at approximately 43,626 miles. Since that time, the vehicle has continued to experience repeated injector failures, control module faults, communication errors, and voltage-related system issues. Current diagnostic codes indicate multiple simultaneous failures including ignition relay feedback circuits, control module power faults, gateway communication loss, brake system communication faults, and battery voltage circuit errors. The dealership has diagnosed a power distribution / fuse block failure at approximately 79,000 miles. These electrical failures affect multiple vehicle systems and raise concerns regarding reliability and potential safety risks due to loss of communication between control modules and possible braking system interaction. The vehicle has been in the dealership numerous times for repairs including engine replacement, injector replacement, control module reprogramming, and electrical diagnostics. I am submitting this complaint due to concern over a potential systemic electrical defect and ongoing reliability issues.
NHTSA complaint #11718551 — an unverified report by a vehicle owner.
My truck is affected by GM’s engine block‑heater safety recall (NHTSA 21V‑496 / GM N212329840) addressing a risk of short circuit and potential engine‑compartment fire at the heater cord/terminal connection. GM’s interim action has been to remove/disable the block‑heater cord, which my dealer did, and then marked the recall “completed.” As a result, the NHTSA VIN tool shows 0 unrepaired recalls, even though no actual repair/restored functionality exists and GM continues to advise owners not to use the block heater until parts are available. Safety concern / impact: I live in a cold‑weather area and purchased this diesel expecting a functioning block heater for reliable cold starts. Disabling the heater has removed an intended cold‑weather safety/starting aid for multiple winters without a final fix. GM’s bulletin explicitly allowed dealers to disable the cord to close the recall, rather than provide a repair, leaving owners without the feature indefinitely. Suspiciously, I have also had to replace glow plugs on this truck sooner than traditional wear / failure rates would demand - including one glow plug that has been replaced twice in short span of time (should have lasted years). I continue to monitor GM’s recall portal; still no parts/remedy schedule. Please review whether GM’s chosen remedy—disabling a safety‑related feature and closing the recall—is adequate and within a reasonable time under the Safety Act. If not, I request NHTSA open a Recall Query into remedy adequacy and timeliness so owners receive a real repair (replacement heater/cord/connector) or appropriate alternative remedies.
NHTSA complaint #11712853 — an unverified report by a vehicle owner.
Driving on the freeway going approx 70 MPH and the ABS warning light, and Stabilitrak warning light suddenly turned on. I’m sure you can imagine how panicked I was going that fast on the freeway and having my brake warnings suddenly turn on. Especially with my entire family in the vehicle with me at the time. Could feel a difference when I was attempting to brake and exit the freeway. Had to apply tons of pressure to get the brake pedal to engage. The cruise control would no longer work, and the trailer brake monitoring system also began flashing. Truck has been to 2 GMC dealerships the ABS module was replaced made it approximately 2 miles and it came back on. Truck is currently waiting for another part to attempt to fix the problem. Truck has 86,000 miles on it.
NHTSA complaint #11705328 — an unverified report by a vehicle owner.
weekly you will start the truck and have no audio of any kind. No blinker noises no collision warning noises, no radio, no on star noise. No sound at all and sound will never come back on until you turn truck off and wait 20 mins. GMC says it's a known software issue, but this has been going on since I bought the truck brand new back is April of 2025. I live in a hands free while driving state when it's come to cell phone use and can't even take a call with no audio of any kind. I don't see how GMC can say this isn't a safety issue.
NHTSA complaint #11699761 — an unverified report by a vehicle owner.
The brake controller on trucks error out while towing. Shuts brakes off. Not a good thing towing 16,000lbs down hill. Almost accident. Destroyed my truck brakes and warped rotors. The controller checks the house battery on trailer and if not in range shuts brakes off. The brake towing screen in truck states all is good but there is this tiny little light at gain adjust location that goes off and you do not have brakes but yet your screen states you do. Bad deal.
NHTSA complaint #11698528 — an unverified report by a vehicle owner.
The transmission control module stopped working leaving the vehicle unable to be driven and no part support from gmc/allison and part is backordered with no eta. There are reports the module becomes defective due to its placement near engine heat. There should be a recall for this issue. Many people are experiencing this issue
NHTSA complaint #11688680 — an unverified report by a vehicle owner.
The contact owns a 2021 GMC Sierra 3500. The contact stated that while his wife had the vehicle idling with the rear defroster activated, shortly afterwards, she observed smoke coming from the plastic on the rear sliding window. After a visual inspection, the contact's wife observed that the plastic was melting, prompting her to deactivate the rear defroster. No warning lights were illuminated. The vehicle was taken to the dealer, who was unable to determine the cause of the failure. The vehicle was not repaired. The manufacturer was not notified of the failure. The failure mileage was 26,000.
NHTSA complaint #11685740 — an unverified report by a vehicle owner.
Driving down the road and I got a service trailer brake code pop up and would not go away and kept dinging It is very distracting and sometimes causes the trailer brakes to malfunction
NHTSA complaint #11676023 — an unverified report by a vehicle owner.
ELECTRICAL SYSTEM: INTEGRATED TRAILER BRAKE CONTROL
The contact owns a 2024 GMC Sierra 3500. The contact stated while driving at approximately 60 MPH and towing a Forest River Riverstone Legacy 5th Wheel trailer, the brake pedal was depressed to slow for oncoming stopped traffic; however, the vehicle failed to respond as needed with the “Service Trailer Brake” warning light illuminated. The contact was able to stop however, the brake pedal had to be depressed to the floorboard to slow the vehicle. The contact had taken the vehicle to a local dealer and was made aware of Customer Satisfaction Program: N232414840 - and replaced the Trailer Brake Power Module (TBPM). The vehicle was repaired; however, the failure reoccurred. The contact returned the vehicle to the same dealer and the Trailer Brake Power Module was replaced a second time. The vehicle was repaired; however, the failure reoccurred. The contact had taken the vehicle to another dealer who diagnosed the vehicle and determined that the failure was with the 5th Wheel RV. The vehicle was not repaired. The manufacturer was informed of the failure. The failure mileage was approximately 20,000.
NHTSA complaint #11672342 — an unverified report by a vehicle owner.
• What component or system failed or malfunctioned, and is it available for inspection upon request? The issue appears to be with the gear shifter assembly and/or park position sensor within the power train system. The vehicle fails to detect that it is in “Park,” even when the gear lever is physically in the Park position. Yes, the vehicle and component are available for inspection upon request. ⸻ • How was your safety or the safety of others put at risk? This malfunction prevents the vehicle from shutting off properly and displays a “Shift to Park” message even when parked. This creates a risk of the vehicle rolling away if the parking brake is not engaged and prevents secure shutdown, potentially draining the battery or creating confusion in an emergency. It compromises both driver and public safety. ⸻ • Has the problem been reproduced or confirmed by a dealer or independent service center? Yes, the issue was reproduced and acknowledged by a certified GMC dealership service department. They noted it is a known issue affecting other GM vehicles but stated there is no open recall or warranty extension currently available for my specific model. ⸻ • Has the vehicle or component been inspected by the manufacturer, police, insurance representatives or others? The vehicle has only been inspected by a GMC-certified dealership. No inspection has been conducted by the manufacturer, police, or insurance representatives at this time. ⸻ • Were there any warning lamps, messages or other symptoms of the problem prior to the failure, and when did they first appear? Yes, a “Shift to Park” message appears on the dash even when the shifter is correctly placed in the Park position. This message began appearing intermittently and has now become a consistent issue over the past few weeks.
NHTSA complaint #11663315 — an unverified report by a vehicle owner.
Battery would not hold charge and would need jump start. Transmission would not stay in gear while towing trailer and would only go to 5th or 6th gear and would jerk out of gear and oil temperatures would go to 225 degrees. Erratically shifting and while driving with cruise control stop with out warning
NHTSA complaint #11662015 — an unverified report by a vehicle owner.
I purchased my vehicle in 2019. Since then, I have had several issues. I've had to replace the coolant reservoir, DEF heater/pump and twice changed the number 8 injector plug. The warning light came on just after the warranty went out. The code reader read the ambient sensor and no sensor.
NHTSA complaint #11661793 — an unverified report by a vehicle owner.
My truck has the shift to park issue and won’t allow me to shut the vehicle ignition off and I cannot shut the vehicle ignition off and it is unsafe and keeps me trapped in my vehicle. I have noticed that it is a common issue and recall on many gmc trucks and I took it to the dealership and they are not wanting to cover it with my two warranties I have on the truck and my vehicle is unsafe. I cannot park the vehicle and shut it off. When I go to put the truck in park on shift column lever, it says shift to park on dash and I turn it on and move shifter to drive and neutral and the vehicle still won’t allow me to shut it off and it shows the same issue.. the issue just began out of no where.
NHTSA complaint #11660511 — an unverified report by a vehicle owner.
The contact owns a 2024 GMC Sierra 3500. The contact stated that the exterior lights of the vehicle were flashing erratically, and the tailgate was opening unintendedly. The contact stated that while driving at various speeds, the vehicle experienced erratic transmission shifts, and the vehicle was jerking and made an abnormal clunking sound. The check engine warning light was illuminated. The contact pulled over to a truck stop and parked the vehicle. The contact stated that the battery became fully drained while parked with the windows rolled down in snowy weather. The contact stated that after waiting 6 hours for AAA to arrive, the vehicle jump-started. The contact stated that the battery had drained on several occasions. The vehicle was taken to the dealer, where it was diagnosed that the two batteries needed to be replaced. The vehicle was repaired; however, the failure persisted, and the vehicle overheated while driving. The contact stated that GMC OnStar was contacted and informed the contact that diagnostic trouble codes related to the transmissions were retrieved. The vehicle was taken to another dealer Weston Buick GMC (22555 SE Stark St, Gresham, OR 97030) to be diagnosed. The vehicle was being diagnosed. The vehicle was not repaired and remained out of the contact's State of residence. The contact related the failure to an unknown recall; however, the VIN was not included. The manufacturer was notified of the failure and covered vehicle rental expenses that allowed the contact to return to their residence. The contact stated that the vehicle was used for load transportation, and the failure had caused both the contact and her husband to be stranded while delivering loads, which caused lodging expenses and loss of wages. The failure mileage was unknown.
NHTSA complaint #11658498 — an unverified report by a vehicle owner.
Trailer brake system connection warning Intermittent when towing it will say trailer not connected, while still having a secure 7 pin connection. This causes me to loose trailer brakes. My camper is nearly 14,000 lbs. Very dangerous situation. Happened since new. Was into / complained to GM service dept over 6 times.
NHTSA complaint #11657477 — an unverified report by a vehicle owner.
When carrying the electronic key in my pocket the vehicle will lock/unlock presumably due to the remote contacting other items in the pocket. I have owned well over a dozen GM vehicles and never had this issue. I believe the remote design has the lock/unlock buttons too proud of the surrounding surface
NHTSA complaint #11647111 — an unverified report by a vehicle owner.