2021 GMC Sierra 2500 Electrical system Problems
- Complaints
- 6about this part
- Share
- 12%of 52 total for the year
- Median mileage
- —not reported
- Trend
- Not enough dataFewer than 15 complaints, too few for a reliable trend.
NHTSA recorded 6 complaints about the electrical system of the 2021 GMC Sierra 2500, 12% of the 52 complaints for this model year. 1 of these say a crash was involved, 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.
“When I’m in reverse the up the cameras turn off. On one incident I was backing up and the camera turned off causing me to back up into the wall of my house”
NHTSA complaint #11686699, filed 2025-09“Headlights and turn signals failed. Flickering of various lights (Daytime running lamp, low beam, high beam, turn signals) followed by total failure. 3700 dollar repair at dealer to replace both headlamp assemblies. Barely over miles of warranty, but still in the 3 year warranty time period. Not having forward lighting is of course a major safety issue. Vehicle should be recalled. Many others are having the issue.”
NHTSA complaint #11633825, filed 2025-01“The harness that hooks to bumper plug for trailer lighting is not completely water tight. Allows water in and creates buildup that weakens the connection as well as allows the plug wire connection to snap out and push out from the pin. Further inspection it was causing a short in the system. I attempted to clean and put some-electric grease on the plug to help clean it but then relaized 3 pins were broken and pushed back.”
NHTSA complaint #11576141, filed 2024-03“While driving the entire dash cluster (speed,rpm etc) turns off entirely, reloads as if truck is just starting with all lights coming off and on, needles cycling max/min. Unable to recreate on command, multiple others reported same issue with no cause/cure listed.”
NHTSA complaint #11570651, filed 2024-02“On 11/21/24 noticed passenger headlight day light running light flickering. On 11/22/24 right turn indicator intermittent fast blink, dash message stated turn indicator failure. Once home, inspected passenger headlight assembly. Found DRL, turn signal, and low and high beam head lights were inoperative. On 11/25/24 went to GMC dealer/service. Staff seemed aware of issues and stated they are common, that they carry the $1,400 sealed assebly in stock. Vehicle is 4 months over warranty, but only has 29,000 miles. …”
NHTSA complaint #11627389, filed 2024-11Related 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 | 5 | 38% |
| 2025 | 1 | 4% |
| 2024 | 33 | 31% |
| 2023 | 6 | 18% |
| 2022 | 12 | 27% |
| 2021 | 6 | 12% |
| 2020 | 13 | 16% |
| 2019 | 9 | 28% |
| 2018 | 7 | 20% |
| 2017 | 6 | 16% |
| 2016 | 9 | 15% |
| 2015 | 11 | 12% |
| 2014 | 4 | 13% |
| 2013 | 3 | 7% |
| 2012 | 4 | 13% |
| 2011 | 9 | 14% |
| 2009 | 7 | 23% |
| 2008 | 3 | 5% |
| 2007 | 5 | 6% |
| 2006 | 4 | 6% |
| 2005 | 42 | 37% |
| 2004 | 48 | 34% |
| 2003 | 36 | 23% |
| 2002 | 1 | 1% |
| 2001 | 4 | 3% |
| 2000 | 3 | 6% |
| 1999 | 2 | 6% |
| 1998 | 1 | 7% |
Other parts of the 2021 GMC Sierra 2500
13 complaintsExterior lighting
9 complaintsEngine
8 complaintsBrakes
7 complaintsBody and structure
5 complaintsLatches, locks and linkages
4 complaintsForward collision avoidance
3 complaintsOther or unknown
3 complaintsAir bags
2 complaintsFuel system
2 complaintsBack-over prevention (rear camera)
1 complaintsLane departure
1 complaints
← All problems reported for the 2021 GMC Sierra 2500
About this data. Data from NHTSA (ODI) complaints, recalls, TSBs and investigations, updated Oct 28, 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