2025 GMC Sierra EV problems

Filed Oct 28, 2026 · Acceleration, Driver assistance · OK · 1 injury

Repeated failures on my 2025 GMC Sierra EV. The truck shows 'Service High Voltage Battery' and the high voltage battery makes a high-pitched hissing noise; it has thrown battery errors twice. The A/C has failed repeatedly; this summer a passenger in the truck overheated and suffered heat stroke because the A/C was not working. Super Cruise and other driver safety features consistently fail while driving. The GPS/telematics module has failed (GPS never finds a location). The truck was at Bob Howard GMC in Edmond, OK from [XXX] to [XXX] (repair order [XXX], 41 days) for the telematics module and A/C, and went back on [XXX] for the A/C and battery and is still in the shop. GM case number [XXX]. No crashes. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Filed Oct 2, 2026 · Driver assistance · 9,800 miles · NJ · crash · 1 injury

The contact owned a 2025 GMC Sierra EV. While the contact’s husband was driving 69 MPH, the Super Cruise control feature became inoperable. The driver dozed off while operating the vehicle, and there was no audible alert to alert the contact. The contact stated that due to the failure, the vehicle traveled through an intersection, crossed over other lanes, and crashed into a guardrail. The air bags deployed during the crash. The contact sustained bruise on the arm and scratches in the crash. A Police report was filed. The vehicle was towed to a service center and was deemed a total loss by the insurance company. The contact stated that the super cruise feature should have alerted the driver. The contact stated that the vehicle failed to recognize the driver’s condition or intervene to prevent the crash by stopping the vehicle. The failure mileage was 9,800.

Filed Aug 4, 2026 · Visibility · FL

The HVAC airflow-direction system failed and no longer correctly controls where the air is directed. Even when the windshield defrost setting is not selected, the system continuously sends airflow toward the windshield. This unwanted airflow causes condensation and fogging on the windshield that cannot be turned off or redirected, impairing the driver's visibility and creating a significant safety hazard. The airflow is also defective in the other ventilation zones. Air is not consistently directed to the selected dashboard, floor, or other vents, and the HVAC system does not operate as designed. This results in poor climate control and significant discomfort for the driver and passengers. The defect has been confirmed by an authorized GMC dealership. The vehicle has remained at the dealership awaiting warranty repair because the required replacement part is unavailable. General Motors has not provided a repair completion date or an estimated delivery date for the replacement part. I have found reports from other owners describing the same HVAC airflow-direction failures on GM electric pickup trucks built on the same platform. The vehicle is currently available for inspection.

Filed Jan 28, 2026 · Electrical, Engine · WI

Vehicle electrical propulsion system became inoperable creating a hazard to occupants in a temperature control required climate Vehicles visual control showing speed and all other information went completely black while vehicle was in motion.

Filed Aug 2, 2025 · Visibility · IA

The passenger side outside rear view mirror does not provide for a clear view on the passenger side of the vehicle. The adjustments on the mirror cannot be set to reduce or eliminate a blind spot on the vehicle. The mirror is not like a normal mirror from other vehicles. I have almost hit several vehicles due to the lack of clear view with the mirror. To give an idea of the blind spot, a vehicle can be seen in the rear view mirror but not seen in the side view mirror or it gives a false distance of where the vehicle is on side mirror. There is no verbiage on the side view mirror of objects appear closer like other mirrors do.

Filed Jul 1, 2025 · Brakes, Driver assistance · AL

My 2025 GMC Denali EV has experienced repeated safety-critical issues, including severe torque pull under acceleration, making it difficult to maintain safe lane position and compromising steering control. This behavior persists even after inspection and is documented on video. The vehicle has also had repeated service brake assist faults, including one critical failure at under 6,000 miles and additional incidents that resulted in me being stranded out of state. Additionally, I have experienced ghost braking while reversing, where the vehicle unexpectedly applies brake force even when parking assist features are manually disabled. I have performed comparative testing with an identical Denali EV loaner (same year and build), as well as three dealership test units, all of which exhibited proper steering stability and regenerative braking behavior. My vehicle’s issues are therefore not “normal operation” but clear, reproducible defects that affect both safety and expected vehicle performance. These issues raise major concerns for real-world safety scenarios requiring immediate acceleration (e.g., merging onto highways or avoiding fast-approaching vehicles). My documented comparative evidence and repeated attempts to have the defects addressed have not resulted in a safe resolution.

Filed May 14, 2025 · Visibility · WA

The passenger rear view mirror is completely flat, not concave like every other mirror we’re used to on a passenger vehicle. This mirror glass is only used on the passenger mirror of the EV trucks for some unknown reason. It is completely unsafe in such a large truck without huge blind spots. Because it appears to be zoomed you can completely miss cars otherwise viewable in blind spot. This also makes setting the passenger mirror up for towing very challenging and also dangerous. In addition the software for the backup titling mirrors works as designed for about 20 seconds and then while still backing moves the mirrors back to the normal position making backing a trailer for example dangerous.

Filed Apr 15, 2025 · Transmission · CO

Failure in the lithium-Ion battery system. Battery conditioning system failed to manage heating and cooling of the battery system leading to catastrophic system failure. Dealership and manufacturer are unable to make repair leaving the vehicle un-operable.

Filed Jan 17, 2025 · Fuel system · MD

Battery heating module failed. This resulted in small, hard to distinguish, "service vehicle" icon to appear on the dash with no further information. This warning icon first appeared during a long drive, then went away on its own and eventually came back. This failure would eventually make charging, particularly in cold weather, impossible and potentially stranding the occupants. The servicing dealership has confirmed this failure and is attempting to replace the module. However, parts for this replacement seem to be unavailable with no current estimated arrival.