Electrical System Related Problems of the 2023 GMC Sierra 3500

Table 1 shows one common electrical system related problems of the 2023 GMC Sierra 3500.

Table 1. Electrical System related problems of GMC Sierra 3500

Problem Category Number of Problems
Electrical System problems
4

Electrical System problem #1

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.

Electrical System problem #2

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.

Electrical System problem #3

We’ve had issues with the electrical system/brake lights when we hook any trailer (horse/boat/utility) to the truck. One issue is that the system shows unconnected and the trailer lights blink or do not work. We’ve brought this in to the dealer 3 times and they have yet to resolve the issue. The other issue of melted plastic on our rear sliding mirror. It just appeared one day, possible after using the rear defog button. We took it to the dealer and they also do not know what is the issue. We found several other blogs where owners have had the same issue. This is a newer vehicle, and we live in southern California where the temperature is mild. It just appeared one day. We are concerned this is a safety issue with the electrical system melting the plastic and possibly causing a fire. Here is a link to a blog: [xxx] lastly, this vehicle was advertised as having adaptive cruise and it does not have the capability (chip) to do so. Information redacted pursuant to the freedom of information act (foia), 5 u. S. C. 552(b)(6).

Electrical System problem #4

There are 2 issues with this vehicle: #1) the rear window defrost causes an electrical issue that melted the plastic on our rear sliding window. Dealer claims we put something hot against the window but we did not. This appeared after we used the rear defrost. Several other owners have complained about this as well. #2) the vehicle is advertised as having adaptive cruise but it does not have this feature.


Electrical System related problems in other GMC Sierra 3500 model year vehicles:



Sierra 3500 Service Bulletins
Sierra 3500 Safety Recalls
Sierra 3500 Defect Investigations