2024 GMC SIERRA 3500 Electrical System Problems

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...

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

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....

Car will not turn off and will display "Shift to Park". Similar recall on other models. This has gotten worse and happens most of the time now.

On at least 5 occasions, my inner tailgate has released itself and gone down during motion. This has been uncommanded. It appears GM has a recall for this but it does not include my truck. The dealership that looked into it agrees this is likely the same issue and GM should include it in the recall.

On multiple occasions, the vehicle has suffered from a severe computer failure. This results in the driver information center losing all data, the climate system shutting down, loss of all driver assistance features, loss of computer based safety systems, and prevents the vehicle from shutting down or being restarted until the batteries are disconnected. This results in the driver having no information about speed or engine parameters while driving. This error has not been reproducible by the dealer however they were able to assess it while one error occurred while driving by them. Their diagnostics show a complete failure of all 3 data buses and failure of the serial data gateway. Troubleshooting thus far has been unsuccessful. During the failure, all errors possible are lit on the warning lamps and the driver information center displays warnings for all vehicle modules. The attached photo was taken during one of the events...

The in cab brake controller does not work with electric over hydraulic trailer brakes. In my research to diagnose and fix the problem I find out GMC has known about this for years and has done nothing to correct. I pulled code C1114 and GMC issued a bulletin for part number (K58-036-00) which I purchased and still did not correct this issue. In short there are many 3500 trucks out there running with no trailer brakes. Here is the worst of this problem. If brakes are tested at a stop they appear to work perfectly however once driving this is when the error code is delivered to the truck so the brakes work at a stop when not needed and do not work under driving when they are needed. GMC has ignored this for years and after spending more of my hard earned money for a fix that did not...

Vehicle caught fire minutes after remote starting. Fire appears to have started on firewall on the left side. We were about to take our kids to school vehicle could have easily caught our house and other property on fire. We did have the check engine light come on occasionally but it would always turn back off, vehicle only had about 12000 miles. Also none of the outlets inside the vehicle never worked.

Hello, I purchased my 2024 GMC 3500 AT4 Seirra late October 2023. Since the purchase date, I have been informed by motorist while at intersections my tailgate was down. I thought I was doing something wrong. On 3/3/2024 I was preparing to wash my truck and noticed my front amber lights were on surrounding my headlights. the vehicle was off, and my keys were in the house. Then my tailgate opener activated on at least 10 - 12 times. The tonneau cover is tight so the tailgate can need assistance opening. Nevertheless, the tailgate has opened on a number of occasions and my two front amber lights came on at least once. I reported this to my dealership on [XXX]. they said my truck has not been recalled yet but to watch this and if it progresses to call them. I noticed a small dent in the top rail of...