2021 Chevrolet Blazer electrical system problems

Related recalls

No recalls on file.

What owners say

1. Filed Oct 1, 2026NYElectrical System

   The main instrument cluster where the speedometer and fuel gauge etc etc reside went blank during operation of the vehicle. I wasn't able to pull over safely until my destination was reached. Restarting the car seemed to "solve" the issue.

   NHTSA complaint #11768271 · source
2. Filed Sep 2, 202668,400 miSCTowedElectrical System

   The contact owns a 2021 Chevrolet Blazer. The contact stated that while driving 40 MPH, the vehicle stalled and was unable to be restarted. The vehicle was towed to the residence. The husband was a mechanic and discovered the 350-amp fuse failure. The fuse was replaced, and the vehicle was repaired. The dealer was not contacted. The manufacturer was made aware of the failure by phone. The failure mileage was approximately 68,400.

   NHTSA complaint #11761571 · source
3. Filed Jun 22, 2026INDriver Assistance & Safety TechElectrical SystemEngine

   The thermometer and thermometer sensor are glitching . The engine temp needle will not rise at all, the engine fan will run the whole time driving and then when it is turned off will run for 10 min . Right before this happens a notice shows the guided steering is being limited. I disconnected the battery and it reset , I drove and there were no issues , next time I started my car the engine temp needle stayed down and the van started again. This car has 36k miles on it. I…

   NHTSA complaint #11745573 · source
4. Filed Jun 6, 2026WAElectrical System

   Lost coolant temp so replaced sensor with one from auto zone and worked for one then pegged to cold again fan runs 100% so went and bought another coolant temp sensor from Chevrolet installed that worked two pegged back to cold again fan 100% now going to pay $700.00 dollars to remove the two sensor wires for the harness all the two the Ecm heard with it being wrapped in the coil wires it gets electromagnetic static due to degradation of wires. Also Radiator started leaking…

   NHTSA complaint #11742425 · source
5. Filed Apr 12, 2026WIElectrical SystemEngineTransmission & Drivetrain

   Once I turn the vehicle off, there is a loud sound coming from the engine area that sounds like a fan. Then the first incident of the fan ongoing after the vehicle was powered off, a battery light was on the internal driver dashboard and stayed on. The battery was recently replaced during 2026 so the battery should not be anywhere near dead, dying, or needing to be checked

   NHTSA complaint #11730609 · source
6. Filed Mar 25, 202650,000 miMAElectrical System

   The contact owns a 2021 Chevrolet Blazer. The contact stated that while attempting to start the vehicle, several unknown warning lights illuminated, and other lights inside the vehicle flashed on and off. The contact stated that the failure also occurred while driving at various speeds. A dealer was contacted. The vehicle was taken to several dealers for diagnostic tests; however, the diagnostic result was unknown. The manufacturer was notified of the failure and informed…

   NHTSA complaint #11726942 · source
7. Filed Feb 19, 2026CAElectrical SystemEngineTransmission & Drivetrain

   This submission is an additional report related to NHTSA complaint #11714381. At approximately 55,000 miles, my 2021 Chevrolet Blazer experienced a sudden throttle body failure while driving. The vehicle entered reduced engine power/limp mode without warning and acceleration was significantly limited. This created a safety concern while driving in traffic, particularly when merging and crossing intersections. Diagnostic code P2101 (Throttle Actuator Position Performance) was…

   NHTSA complaint #11719088 · source
8. Filed Jan 30, 2026CAElectrical SystemEngineTransmission & Drivetrain

   Around 55,000 miles, my 2021 Chevrolet Blazer experienced a throttle body failure. The check engine light illuminated and the vehicle entered a reduced power/limp mode condition. Throttle response was significantly limited, and the vehicle could not accelerate normally. While the vehicle remained drivable, it took substantially longer to reach speed, which could pose a safety risk when merging into traffic or crossing intersections. Diagnostic trouble code P2101 (Throttle…

   NHTSA complaint #11714381 · source
9. Filed Dec 9, 2025TXElectrical System

   "Steering assist reduced" message was displayed. At the same time the temperature gauge stopped working and after I shut the car off, the motor fan ran full force for 10+ minutes. Shows no check engine light.

   NHTSA complaint #11703920 · source
10. Filed Nov 16, 2025NCElectrical SystemEngineFuel, Hybrid & EV Propulsion

    Car was running fine yesterday, today does not want to start. Thought it was the battery, bought anew battery. Still wouldn't start. Rest of cat is getting great power. Code reader is reading its a fuel pump control moduler which just so happens to be in an open recall for my exact year of vehicle yet my vin number does not pop up on the GMC website under active recall. I have a 2021 chevy blazer .

    NHTSA complaint #11699684 · source
11. Filed Nov 3, 2025MIElectrical SystemEngine

    Action Required "Steering Assist Warning" drive with caution, Temp gage reads cold, A/C stops working, engine cooling fan runs on high speed (even after the engine is shut off), pending P2018 code, with no Check Engine Light (CEL). Replaced Engine coolant Temperature (ECT) sensor, problem did not go away. Several reviews suggest to replace the thermostat, check fuses for proper insertion, reroute ECT wiring, and possibly replace radiator. Most of these repairs can be very…

    NHTSA complaint #11697313 · source
12. Filed Oct 15, 2025CAElectrical System

    In March after a short drive, 24 miles, the car temp was pegged at Cold. After turning off the car, the fan continued to run several minutes. After a quick internet search several posts commented on a similar issue with their vehicle. Two potential issues were identified - thermostat failure or programming issue. With less than 40,000 miles on the car, I purchased a diagnostic tool. Running the tool program two errors were identified. After resetting the sensors, the problem…

    NHTSA complaint #11693729 · source

Source: U.S. National Highway Traffic Safety Administration (NHTSA) Office of Defects Investigation public data. Complaints are submitted by owners and are not verified by NHTSA or by us; a complaint does not prove a defect exists. View this vehicle on NHTSA.gov Methodology