2020 GMC Sierra 3500 Electrical system Problems
- Complaints
- 9about this part
- Share
- 18%of 51 total for the year
- Median mileage
- —not reported
- Trend
- Not enough dataFewer than 15 complaints, too few for a reliable trend.
NHTSA recorded 9 complaints about the electrical system of the 2020 GMC Sierra 3500, 18% of the 51 complaints for this model year. 1 a fire, according to the filers.
Fewer than 15 complaints name this part, so treat the figures as a rough indication only.
Example complaints
Selected from NHTSA records; personal details are removed. They are consumer reports, not findings.
“The computer malfunctions. It is available for inspection. The computer lights up and causes failure in the trailer brakes. Glenn Polk the dealership in Sanger Texas has been working on a fix but has yet to come up with one. I have spoken with General Motors Representatives several time trying to resolve the problem without result. I also emailed the CEO last Friday and have heard nothing. There were no warning lights until seconds before failure.”
NHTSA complaint #11418543, filed 2021-05“The computer lights up the dash reducing power and turning off power to trailer brakes. This has almost caused an accident on several occasions . It happens a couple of times per trips. This vehicle has been in the shop a couple of times per month since it was put into service. Glenn Polk Chevrolet has worked on it each time and the problem is still there. This truck has also had several injector issues. There is an open case with this vehicle with General Motors with no resolution. I have filled out forms on each of my 2020 GMC's 3500's.”
NHTSA complaint #11418621, filed 2021-05“The component that failed was the passenger side or main battery. Our safety was compromised when the design of the HVAC system and the battery location allowed the hydrogen sulfide gas into the passenger compartment of the vehicle. The issue has not been confirmed by a deal or independent service center. The battery(s) and vehicle are available for inspection to confirm the issue. I have uploaded pictures of the battery and one can visually see the swollen battery with liquid leaking out of it. There were no warning messages or other symptoms prior to the failure. …”
NHTSA complaint #11471359, filed 2022-06“Infotainment system AND center instrument cluster went completely black - six times over the course of one month. I took the truck to Alan Webb Chevrolet in Vancouver Washington. Their service technician was aware of infotainment system “Black Screen of Death - BSD” problems due to previous repair work on several different GM models. However, on the way to their Service Department to get this fixed, I rolled down the driver’s side window about 6 inches to get some fresh air and rolled it back up. Out of nowhere the Infotainment system AND the center instrument cluster came back to life. …”
NHTSA complaint #11440826, filed 2021-11“The computer lights up dash reducing power and taking the trailer brakes away. This almost caused a wreck when the truck shut off and the brakes failed. This truck has been in the shop at least once per month trying to fix the issues, from computer and brake failure to injector failure. Glenn Polk Chevrolet in Sanger has been working on this since the truck was new. Also we have case open with General Motors without resolution. The dash lights up at the same time as the brakes fail.”
NHTSA complaint #11418617, filed 2021-05Related service bulletins
- 11024486May 16, 2025This bulletin advises the tech to inspect deeper into what may be to main cause of an engine failure.
- 11019017Apr 10, 2025This bulletin provides a procedure on how to check for a battery drain utilizing the Picoscope and how to measure the load on the system that may be causing a drain.
- 11017595Apr 3, 2025This service bulletin provides information on the proper Reflective High Temperature Heat and/or Insulating Tape to use for certain repairs, such as Wiring Harness Repairs.
- 11017244Mar 31, 2025The intent of this service bulletin is to identify aftermarket ALDL or DLC interface devices as potential sources for causing multiple customer concerns that do not have other…
- 11017255Mar 25, 2025This service bulletin helps diagnose/reduce possible CCND issues on Transfer Cases - Service 4WD on DIC, Intermittent Failures, Noise Concerns, Driveline/Steering…
- 11017207Mar 21, 2025This service bulletin provides information for dealers/technicians on Service Programming System (SPS) Error Codes E4398, E4399, E4401, E4403, M4404, M4413, M6954, M6955, E4414…
- 11017031Mar 12, 2025This service bulletin provides information to diagnose batteries that have set for a long period of time and/or cold weather climates and testing those batteries.
- 11014579Feb 19, 2025This technical bulletin provides repair information to correct a customer concern of Diagnostic Tips For Park Assist Off Message / Unwanted Or False Park Assist Alerts / No DTCs.
- 11014230Jan 31, 2025This bulletin advises the dealers to maintain the vehicle stock on hand by doing a full inspection on the vehicles before being sold (prepping) to the customer.
- 11014239Jan 29, 2025This service bulletin provides information on the Transport Mode Feature, also known as Logistics mode, which is used to increase the 12V Battery stand time of the vehicle during…
Electrical system: other model years
| Year | Complaints | Share of year |
|---|---|---|
| 2026 | 1 | 20% |
| 2025 | 3 | 18% |
| 2024 | 16 | 31% |
| 2023 | 4 | 14% |
| 2022 | 7 | 22% |
| 2021 | 4 | 20% |
| 2020 | 9 | 18% |
| 2019 | 3 | 23% |
| 2018 | 2 | 14% |
| 2017 | 3 | 23% |
| 2016 | 2 | 11% |
| 2015 | 6 | 19% |
| 2014 | 1 | 14% |
| 2013 | 1 | 7% |
| 2012 | 2 | 22% |
| 2011 | 2 | 10% |
| 2009 | 1 | 20% |
| 2008 | 1 | 4% |
| 2007 | 2 | 13% |
| 2005 | 3 | 13% |
| 2004 | 5 | 21% |
| 2003 | 1 | 14% |
| 2001 | 1 | 3% |
| 2000 | 1 | 4% |
| 1999 | 1 | 5% |
| 1998 | 1 | 8% |
Other parts of the 2020 GMC Sierra 3500
19 complaintsBrakes
7 complaintsEngine
6 complaintsFuel system
6 complaintsOther or unknown
6 complaintsBody and structure
5 complaintsTires
4 complaintsVisibility (wipers, defrost, mirrors)
2 complaintsAir bags
1 complaintsEngine cooling
1 complaintsExterior lighting
1 complaintsForward collision avoidance
1 complaints
← All problems reported for the 2020 GMC Sierra 3500
About this data. Data from NHTSA (ODI) complaints, recalls, TSBs and investigations, updated Oct 30, 2026. Complaints are unverified consumer reports and may be duplicated or inaccurate.
To check a specific vehicle for open recalls, use its VIN at nhtsa.gov/recalls. Methodology