2021 Chevrolet Blazer Problems & Owner Complaints

Electrical System 37

“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 just bought it 2 days before it started happening”
NHTSA complaint #11745573, 2026

“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 after couple years but they want $3100.00 dollars for that.Was told extended warranty ran out three days before they dis…”
NHTSA complaint #11742425, 2026

“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, 2026

Engine 36 1 fire

“My car caught on fire for no apparent reason. Front of car totally destroyed.”
NHTSA complaint #11502601, 2023 · fire

“The thermostat malfunctioned causing an error message regarding “steering assist is reduced”. When I parked and turned off, the engine fan continued to run. When car was restarted, the temp gauge inside was stuck at C. Took to dealership and they assessed. They repaired the thermostat under power train warranty, however there was a crack in the radiator (top) resulting in the need for a new radiator. This vehicle had 35,000 miles on it. Upon research online, it seems there are MANY people who have had this same issue and worse. It appears cars produced during COVID era are most affected…”
NHTSA complaint #11745926, 2026

“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 just bought it 2 days before it started happening”
NHTSA complaint #11745573, 2026

Unknown Or Other 20 1 fire

“My car caught on fire for no apparent reason. Front of car totally destroyed.”
NHTSA complaint #11502601, 2023 · fire

“At 48,000 miles, check engine light came on and loud fan sound continued after turning car off. Took car to dealership where I was informed I needed a new radiator and it is not covered by warranty.”
NHTSA complaint #11721657, 2026

“I am reaching out regarding an ongoing issue with my 2021 Chevrolet Blazer. The vehicle is experiencing a noticeable stutter or hesitation when shifting between second and third gear. In addition, there are instances where the vehicle accelerates unexpectedly or more aggressively than intended. This behavior is particularly concerning, as it presents a potential safety issue during normal driving conditions. These concerns have become increasingly noticeable, and I am concerned they may indicate a transmission or related mechanical problem that requires prompt inspection and resolution. Ple…”
NHTSA complaint #11735127, 2025

Power Train 18

“The contact owns a 2021 Chevrolet Blazer. The contact stated that while driving at an undisclosed speed, the accelerator pedal was depressed, and the transmission was slipping gears before the vehicle lost motive power. The contact stated that the vehicle failed to drive forward or move while in reverse. The check engine warning light was illuminated. The vehicle was towed to the residence. The contact, who was an independent mechanic, diagnosed the failure as a clutch solenoid failure. The contact stated that the transmission needed to be replaced. The vehicle was not repaired. The contact re…”
NHTSA complaint #11751752, 2026

“The thermostat malfunctioned causing an error message regarding “steering assist is reduced”. When I parked and turned off, the engine fan continued to run. When car was restarted, the temp gauge inside was stuck at C. Took to dealership and they assessed. They repaired the thermostat under power train warranty, however there was a crack in the radiator (top) resulting in the need for a new radiator. This vehicle had 35,000 miles on it. Upon research online, it seems there are MANY people who have had this same issue and worse. It appears cars produced during COVID era are most affected…”
NHTSA complaint #11745926, 2026

“The transmission (powertrain) developed a delay when shifting into reverse, followed by harsh engagement. The condition worsened over time and resulted in a complete loss of reverse. The vehicle will not move when shifted into reverse. This creates a safety risk when parking, backing out of spaces, or maneuvering in traffic, as the driver cannot safely control vehicle movement. The issue occurred at approximately 89,000 miles under normal driving conditions. No warning lights were present prior to failure. The problem was reported to a dealership and diagnosed as a transmission failure. The co…”
NHTSA complaint #11733441, 2026

Service Brakes 18

“Went to park car in a park to drop daughter off and it sputtered out and stalled out of nowhere with no warning. I had received a lamp warning very sporadically prior to this and on occasion that stated 'reduced steering assist drive with care' this resulted in heavy steering for that drive until car was shut off and then it would go away and be fine again, fixed the car through Knudtsen Chevy due to a recall about a month before on the issue with the engine being turned off and it thinking it was still hot and still running the fan (even though the car was not running). Knudtsen fixed that i…”
NHTSA complaint #11734510, 2026

“Brake booster failed after 50k miles needing repair. Brake became very still, prolonging the time it takes to stop the vehicle”
NHTSA complaint #11688584, 2025

“My name is [XXX] and I was a passenger in our 2021 Chevy Blazer with our young child in the back seat when the brakes suddenly failed while we were driving on the freeway. The brake pedal went stiff and wouldn’t respond. It was terrifying — we truly felt like we were going to crash. I was panicked, and my child was crying. Since then, I’ve been too afraid to drive or ride in this vehicle, even if it gets repaired. This isn’t the first issue with the car, and GM has not resolved it in a timely or helpful way. The vehicle is currently at the dealership and we are paying for a rental car out o…”
NHTSA complaint #11677356, 2025

Fuel/Propulsion System 16 1 crash

“On Friday, April 28, 2023, at about 11:30 am, my car, died as I was driving it out of the grocery store parking lot; luckily, it didn’t happen as I was crossing the busy highway. I attempted several times to restart it, with no luck. There were no warning lamps, messages or other symptoms of this problem. The vehicle was in the middle of an aisle, blocking the aisle and many cars in parking spots, so I managed to get it into neutral and it backed around into parking spaces where the left rear quarter stopped against the front tire of a Ford F-350. I was actually thankful for the truck as I…”
NHTSA complaint #11525703, 2023 · crash

“XXX the car had gas, turned over, but would not start. I had it towed to a repair center who towed, did diagnostics and came up with the codes for a bad fuel pump control module. It was replaced and the car starts. There was no warning. Problem was confirmed by an independent service center. All documentation is available. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)”
NHTSA complaint #11749347, 2026

“fuel pump control module failed at 26000. recall number N252516900. This is a recall that other 2021 blazers have ben part of. Over 300000 recalls so far. GM says my car isn't. Ridiculous. They dont want to acknowledge their fault. I need a formal statement that this module should be recalled for my car.”
NHTSA complaint #11749371, 2026

Steering 15 1 crash 1 injury

“The contact owned a 2021 Chevrolet Blazer. The contact stated while driving 69-70 MPH, the steering wheel strongly pulled to the left side and into the roadway median. There was no warning light illuminated. The contact stated that the vehicle hit the median and bounced, facing incoming traffic. The contact slammed on the brakes and shifted into park (P). The air bags deployed. The contact was able to exit the vehicle with the assistance of bystanders. Emergency services arrived at the scene but the contact was not transported to the hospital at the time. The contact later received medical ass…”
NHTSA complaint #11539220, 2023 · crash · 1 injury(ies)

“The vehicle showed an error on the dash which stated "Action Required Steering Assist is Reduced Drive with Care" I tool the vehicle to the dealer I purchased it from McClusky Chevy at Kings Auto Mall in Mason Ohio. They informed me that the error code is C0460:58 and GM has a service bulletin 20-NA-215 which advises to replace the Steering Gear due to internal component interference. No one explained to me that this could cause catastrophic failure and lead to a crash before I left the dealership. They could not replace it as they said they do not have the part and it is on national backo…”
NHTSA complaint #11738765, 2026

“In September 2023, when getting my vehicle serviced for a routine oil change, I was told there was a leak in my radiator. They replaced the entire thing under warranty. On November 15th, 2025, while driving on the highway heading home from out of town with my children, an error flashed up saying “steering assist is reduced – drive with care” Upon arriving home, the fan on my car was running on high for a solid 10 minutes after turning the car off. No recall but Special Coverage N252508350 covers the thermostat replacement. Upon inspection by a mechanic, I was informed that the radiator is al…”
NHTSA complaint #11701205, 2025

Forward Collision Avoidance 7 1 crash 1 injury

“The Esc display came up then sutbality sensor show and my back wheel went right. My car flipped twice and then landed on the guardrail.”
NHTSA complaint #11539221, 2023 · crash · 1 injury(ies)

“Auto braking system went off when I was at stop light & began to move forward (was 2nd in line of cars) and I accelerated. On the roadway, there are construction 'steel plates' laying on the ground in the area that all cars must drive over (I have driven over them in my same Blazer before) because we have no choice. One I pressed on gas & began moving over those plates, the Blazer stopped itself VERY abruptly & jerked my head forward & dash said I had to press on brake let off or something in order to move again - it was all very fast & I had a line of traffic behind me at 5:15 pm on a Friday…”
NHTSA complaint #11685984, 2025

“Brakes bottomed out. Message on my dash board said “Brake System Failure reduce speed to 62” and the brake went on the way to the floor.”
NHTSA complaint #11675890, 2025

Suspension 4 2 crash 4 injury

“Driving on straight road going speed limit. Heard a pop behind me like a tire pop. Car fish tailed uncontrollably and ended up crashing into a Ranch Fence on the right side of the road. 2 of my kids and myself had injuries. When we got off the vehicle witnesses and I saw A rear link broken which keeps the tires straight.”
NHTSA complaint #11737304, 2026 · crash · 3 injury(ies)

“The Esc display came up then sutbality sensor show and my back wheel went right. My car flipped twice and then landed on the guardrail.”
NHTSA complaint #11539221, 2023 · crash · 1 injury(ies)

“The contact owns a 2021 Chevrolet Blazer. The contact stated while driving 35 MPH, the ambient air temperature was stuck on negative forty. The contact replaced the sensor. The vehicle went into ICE/SNOW Mode on several occasions and was not driving as designed. The air conditioner was blowing out hot air. Additionally, the vehicle was pulling to the right while driving. There were no warning lights illuminated. The vehicle was taken to an independent mechanic who scanned the vehicle and determined that the sensor was operating as designed. The mechanic informed the contact that there was a lo…”
NHTSA complaint #11653720, 2025

Tires 4

“Tires - purchased vehicle from car dealership two weeks ago. Drivers side rear tire low. Aired up was low again next day. Blow out On freeway tires are unsafe. Per Discount Tire said tire could not be repaired . all four tired unsafe, tread issue. Replaced two rear tires. Unknown when light came on. Tire size 265/45r21 dot A3LMWD 30”
NHTSA complaint #11533392, 2023

“The contact owns a 2021 Chevrolet Blazer equipped with Continental Tires, Tire Line: Crosscontact LX Sport, Tire Size: 235/65/R18, DOT: (Unavailable). The contact stated that while driving at various speeds and driving over snow covered roads, the rear end was swaying. The tires were wearing from the inside out. The vehicle was taken to the local dealer where it was diagnosed that the tires needed to be replaced. The manufacturer was notified about the failure and offered to assist with the repair. The approximate failure mileage was 14,000.”
NHTSA complaint #11509312, 2023

“The contact owns two 2021 Chevrolet Blazer equipped with Continental Tires, Tire Line: Crosscontact LX Sport, Tire Size: 235/65/R18, DOT Number: A3LMWD30. The contact stated that while his daughter was driving 30 MPH, the vehicle lost traction. The contact stated that the rear driver’s side tire low air warning light was illuminated. The contact stated he also experienced the same failure with his vehicle. The contact stated all eight tires were bald on both vehicles. The contact took both vehicles to the local dealer, where it was diagnosed with needing all eight tires to be replaced. The veh…”
NHTSA complaint #11506194, 2023

Lane Departure 3

“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 just bought it 2 days before it started happening”
NHTSA complaint #11745573, 2026

“"Driver Assisted Reduced Use Drive With Care Message" comes on when it is over 70 degrees outside. The temperature gage reads zero, A/C does not work, when the car is turned off the fan runs on high for an extended period of time. Showing code P0128 Used car purchase, came on 3 days after receiving vehicle from the dealership. Reset the code came on again 2.5 weeks later (5/3/2025) when the outside temperature was in the 70's”
NHTSA complaint #11658644, 2025

“The radio and all the sound notifications such as turn signals, emergency flashers, crash avoidance, cross traffic, lane departure, and the use of the emergency OnStar system do not work. this has been addressed in GM service information #PIT5971B: Loss OF Audio and OnStar LED is Red - (Apr 3, 2023) GM appears to be addressing this as an inconvenience of not having the entertainment of the radio and not the safety features associated with it. This also includes the use of hands-free cell phone.”
NHTSA complaint #11529702, 2023

Air Bags 2 2 crash 2 injury

“The contact owns a 2021 Chevrolet Blazer. The contact stated that while driving at approximately 50 MPH, the vehicle struck a deer, causing severe damage to the vehicle's front end. The contact stated that smoke was coming from the center of the steering wheel; however, the vehicle's air bags had not deployed. The contact was transported to the local hospital and treated for chest injuries. The vehicle was towed to a local collision center. No further information was available. A Police report was filed at the scene. The cause of the failure was not yet determined. The local dealer and manufac…”
NHTSA complaint #11753752, 2026 · crash · 1 injury(ies)

“The contact owned a 2021 Chevrolet Blazer. The contact stated that while driving at 30 MPH, a 2012 Mazda CX-7, allegedly going at 70 MPH traveled through an intersection and crashed into her vehicle. The Mazda later crashed into another unknown vehicle. All the air bags deployed; however, the driver's side air bag exploded in her face. The air bag dust was in the vehicle. The contact was rendered unconscious due to the incident. All the warning lights illuminated after the crash. OnStar was activated and disabled the vehicle. There were unknown fluids leaking from the vehicle. There was no re…”
NHTSA complaint #11700607, 2025 · crash · 1 injury(ies)

Engine And Engine Cooling 2

“The contact owns a 2021 Chevrolet Blazer. The contact stated that upon turning off the vehicle, the fan remained engaged for approximately 10 minutes. Additionally, the contact stated that the A/C system was intermittently inoperable. The contact stated while driving at an undisclosed speed, the vehicle made an abnormal sound, and the contact noticed that there was a coolant leak onto the floor of the vehicle. An unknown warning light was illuminated. The vehicle was taken to East Houston Auto Electric, where it was diagnosed that the thermostat was stuck and needed to be replaced. The vehicle…”
NHTSA complaint #11646473, 2024

“The contact owns a 2021 Chevrolet Blazer. The contact stated that oil was leaking from the vehicle. There were no warning lights illuminated. The vehicle was taken to the local dealer, where it was diagnosed that the cam shaft carrier needed to be replaced. The vehicle was repaired, but the failure recurred. The vehicle was taken to an independent mechanic, who determined that there was a separation in the transmission, oil cooler line, valve, and hoses that needed to be replaced. The vehicle was not repaired. The manufacturer was contacted and submitted a complaint. The failure mileage was ap…”
NHTSA complaint #11587410, 2021

Structure 2 1 fire

“My car caught on fire for no apparent reason. Front of car totally destroyed.”
NHTSA complaint #11502601, 2023 · fire

“To whom it may concern, I own a 2021 chevrolet blazer I have been noticing a very large amount of water on the front floor boards since this discovery the windows being moist in the mornings make sence l. The windshield has been replaced several times with no obvious leaks at this location. There is no visible leaks during heavy rain or car washing, the biggest concern i have it if there's moisture I am more likely to develop electrical problems not to mention the moldy smell in the vehicle. I have done extensive research and found this to be a problem with most Chevrolet Blazer's my question…”
NHTSA complaint #11655504, 2025

Back Over Prevention 1

“The radio and all the sound notifications such as turn signals, emergency flashers, crash avoidance, cross traffic, lane departure, and the use of the emergency OnStar system do not work. this has been addressed in GM service information #PIT5971B: Loss OF Audio and OnStar LED is Red - (Apr 3, 2023) GM appears to be addressing this as an inconvenience of not having the entertainment of the radio and not the safety features associated with it. This also includes the use of hands-free cell phone.”
NHTSA complaint #11529702, 2023

Equipment 1

Exterior Lighting 1

“HEADLIGHTS FLASH OR STAY ON EITHER LOW OR HI BEAM,HATCH OPENS ITSELF, AWD POPING, NOISE IN DASH, SHIFTING INTO AWD BY ITSELF, TRANSMISSION NOT SHIFTING CORRECTLY . THERE IS NO PATTERN AND IT THROWS NO CODES. MAJOR ELECTRIC PROBLEMS. THE KEYLESS ENTRY PAD DIDN'T WORK THE DAY I PURCHASED MY CAR. HAD A NEW ONE INSTALLED 3 PROGRAMS AND NOW ALL THIS STARTED.”
NHTSA complaint #11405457, 2021

Fuel System 1

“The contact owns a 2021 Chevrolet Blazer. The contact stated that while the vehicle was parked, while attempting to start the vehicle, the vehicle failed to start. The vehicle was towed to a dealer where it was diagnosed and determined that the fuel pump module needed to be replaced. The vehicle was not repaired. The manufacturer was not notified of the failure. The failure mileage was approximately 81,123.”
NHTSA complaint #11675829, 2025

Parking Brake 1

“The contact owns a 2021 Chevrolet Blazer. The contact stated that while driving at an undisclosed speed, there was an abnormal sound coming from the vehicle with several unknown warning lights illuminated. The contact stated that the electronic parking brake independently activated. Additionally, the failure had occurred while the vehicle was parked. The failure was persistent. The vehicle was not diagnosed or repaired by an independent mechanic or a dealer. The manufacturer was not made aware of the failure. The failure mileage was approximately 31,000.”
NHTSA complaint #11732946, 2026

Seats 1

“HEADLIGHTS FLASH OR STAY ON EITHER LOW OR HI BEAM,HATCH OPENS ITSELF, AWD POPING, NOISE IN DASH, SHIFTING INTO AWD BY ITSELF, TRANSMISSION NOT SHIFTING CORRECTLY . THERE IS NO PATTERN AND IT THROWS NO CODES. MAJOR ELECTRIC PROBLEMS. THE KEYLESS ENTRY PAD DIDN'T WORK THE DAY I PURCHASED MY CAR. HAD A NEW ONE INSTALLED 3 PROGRAMS AND NOW ALL THIS STARTED.”
NHTSA complaint #11405457, 2021

Traction Control System 1

“The contact owns a 2021 Chevrolet Blazer. The contact stated that while stopped at a railroad track, the vehicle independently stopped and went into crash mode while on the railroad tracks upon acceleration. The contact shifted the vehicle into reverse and then into park. Once the vehicle was placed into drive, the vehicle resumed normal operation. The vehicle was taken to a dealer where they replaced an unknown module and performed a software update. Despite the repair, the contact stated that the failure persisted. The contact also stated that while driving at 40 mph, the traction control wa…”
NHTSA complaint #11423591, 2021

Vehicle Speed Control 1

“For about a week and a half my car had made a high pitched wheezing/hubbing sound when started cold. This occurred at all temperatures cold and warm. Yesterday December 13th I went to run some errands and about a mile into my drive my 2021 3lt 3.6 V6 Chevrolet Blazer lost the ability to power itself. There was no electrical problem however the power train lost power all gears drive and reverse. I was able to get off the roadway without incident. I scan my check engine light and had several check engine lights including a P 0796.”
NHTSA complaint #11705228, 2025

Wheels 1

“Vehicle is available upon request. 5/28/23 tires needed replaced, not even 30,000 miles on car. Customer was charged. 6/13/23 struts and mounts replaced at dealership 3/29/24-Revs high when barely touching pedal. Turned car off and it started back up on its own. Happens at least once a week. Dealership was unable to recreate. 4/1/24- wheel bearing replaced, customer was charged. April 2024 black metal showing through white paint. Paint was thin and fading. Dealership repainted the 2 doors that had paint issues. 12/20/24- Antifreeze level was at bottom of reservoir. Sloshing noise when driv…”
NHTSA complaint #11641205, 2025