Chevrolet Blazer 2020: Retiros, Quejas y Ley de Limón de California

Thermostat stuck open radiator broke. Told by 4 GM Dealerships, this is a very common problem in a GM 3.6L V6. GM even claims it's common in its Tech Advisements. The "Stuck Open" Glitch (P0128 Code)

NHTSA #11738523

Car is overheating with multiple engine codes. Unable to drive. Car power is reduced and shortly after will start overheating.

NHTSA #11738394

I bought this car brand new. 0 miles. I’ve had an oil leak fixed once in it. And now it’s leaking oil again. I have to have it put back in the shop and pay out of pocket once again for now fault of mine. The first time it was leaking from the cam shaft. This is ridiculous. I will also be filing a complaint with Chevy.

NHTSA #11710840

Variable Valve Timing (VVT) exhaust Solenoid engine light has been coming on and turning off immediately for a few months, finally found the issue. $665 replacement.

NHTSA #11740105

The radiator in these cars constantly fails. This can lead to major engine issues. Multiple Chevy owners have reported defects

NHTSA #11740743

Driving down the road at 50 mpg when to car just shut off had a hard time getting it off the road and did still was all the way we almost got hit three times

NHTSA #11717071

I am submitting this complaint regarding my 2020 Chevrolet Blazer and what appears to be a widespread cooling system defect. My vehicle has developed a coolant smell outside the vehicle, which raises concerns about a coolant leak from the radiator. After researching the issue, I discovered that numerous Chevrolet Blazer owners have reported similar coolant-related problems, including radiator failures, coolant leaks, and persistent coolant odors. These complaints are widely discussed across online forums, social media, and owner groups. General Motors appears to be aware of this recurring issue, yet many owners continue to experience failures within and outside of warranty coverage. The coolant smell is concerning because it may indicate a leak within the cooling system, which could lead to overheating, engine damage, loss of vehicle reliability, and potential safety risks while driving. Owners should not be experiencing major cooling system failures on relatively modern vehicles. I request that NHTSA investigate the cooling system and radiator issues affecting the 2020 Chevrolet Blazer and determine whether a defect exists that warrants a recall or other corrective action. The number of similar complaints suggests this may be a systemic issue rather than isolated incidents. General Motors should be held accountable for addressing this widespread problem and providing a permanent repair solution for affected owners. Thank you for your attention to this matter.

NHTSA #11743467

I am submitting this complaint regarding the transmission in my 2020 Chevrolet Blazer. My vehicle has fewer than 100,000 miles and has experienced significant transmission failure symptoms, including hard shifting, jerking during acceleration, RPM fluctuations, slipping, loss of normal power, and inability to safely reach highway speeds. The vehicle struggles to accelerate properly and at times will not shift correctly into higher gears. Diagnostic trouble codes related to transmission operation have been present, including pressure control solenoid and transmission control faults. Repairs have already been attempted, including replacement of transmission-related components, but the transmission continues to malfunction. Through online owner groups, forums, and discussions with other Chevrolet Blazer owners, I have found numerous reports from owners experiencing similar transmission problems in 2019-2022 Chevrolet Blazers. Many owners report transmission slipping, harsh shifting, torque converter issues, valve body failures, pressure control solenoid failures, and complete transmission replacement at relatively low mileage. These failures create a serious safety concern because the vehicle may hesitate, lose power, fail to accelerate properly when entering traffic, or be unable to maintain safe highway speeds. Drivers and passengers are placed at risk when a vehicle cannot respond normally during merging, passing, or other traffic situations. Owners are frequently being quoted between $7,000 and $12,000 for transmission replacement or repair despite the vehicles being relatively new and often having less than 100,000 miles. Many consumers believe these failures indicate a widespread defect rather than normal wear and tear. I request that NHTSA investigate transmission failures in the 2020 Chevrolet Blazer and related model years to determine whether a manufacturing or design defect exists and whether a recall or other corrective action is warranted.

NHTSA #11744816

The contact owns a 2020 Chevrolet Blazer. The contact stated that while driving at an undisclosed speed, the vehicle hesitated with a grinding sound coming from the vehicle, with the check engine warning light illuminated. The contact stated that the vehicle was jerking while driving and while accelerating from a stop. In addition, the contact noticed fuel leaking from the front end of the vehicle while the vehicle was parked at the residence. The vehicle was taken to the dealer, where it was diagnosed that the START/STOP accumulator end cap had failed and needed to be replaced. The vehicle was not repaired. The manufacturer was made aware of the failure and referred the contact to the NHTSA Hotline for assistance. The approximate failure mileage was 157,236.

NHTSA #11704538

The temperature gauge on my 2020 Chevrolet Blazer stopped working and remains stuck on “cold” at all times. At the same time, the air conditioning stopped functioning properly and only blows hot air. The vehicle was taken to a repair shop where diagnostics indicated a faulty thermostat sensor. The thermostat sensor was replaced and the issue appeared fixed. However, less than two weeks later, the same problem returned. The temperature gauge again stays on cold permanently, and the AC blows hot air. This appears to be a recurring issue affecting the vehicle’s cooling system and temperature monitoring

NHTSA #11734563

Vehicle has shift to park light and will not turn off even with the shifter in the park position.

NHTSA #11723443

I got into my vehicle and it said “steering assist reduced. Drive with care”. the A/C stops working and refuses to cool as well as the cooled seats. The thermostat for the coolant reads “C” despite driving it 40+ miles in 83 degree weather. Tried disconnecting battery upon research and finding out many other people are having the same problem. The light turned off and came right back on the following morning

NHTSA #11696282

P0128 code produced when scanned. Cooling fans on high. No ac. Steering Assist Warning. Had to replace the thermostat. ECM also replaced and caused the tire pressure sensors to fail and had to replace the tire sensors. There is a recall on models 2021 to 2025 but none on the 2020 for the thermostat. I have paid $3500.00 to have my vehicle fixed.

NHTSA #11738607

P0128CODE P0024 CODE SECOND Cam Shaft sensor failure Thermostat failure, stuck open Electrical issues from low battery power Failure to shift to park when shutting off vehicle

NHTSA #11739711

"Steering Assist Reduced” warning message appears on dashboard display and temperature gauge stuck on cold on the dashboard display. I understand this such a common issue with the 2019 and 2020 Blazer that General Motors has issued Technical Service Bulletins but refuses to repair these vehicles for free. This is unacceptable! Issue a mandatory recall therefore GM must perform the repairs for free.

NHTSA #11693175

The contact owns a 2020 Chevrolet Blazer. The contact stated that while parking the vehicle and shifting to park(P), the message "Shift to Park” was displayed. The contact turned off and restarted the vehicle several times and shifted from drive(D) to park(P) several times before the message disappeared. The contact stated that the vehicle was also showing electrical failures. The contact stated that after shifting to park(P) and turning off the vehicle, the contact heard chimes as if the vehicle was still running. There was no warning light illuminated. The contact stated that one morning the vehicle had to be jumpstarted and on another morning the battery was completely drained. The battery was taken to an Auto Parts Store to be checked. The contact was informed that the battery was in good operating condition. The contact stated that the battery was drained again and was replaced. The contact had not taken the vehicle to a local dealer or independent mechanic to be diagnosed or repaired. The manufacturer was informed of the failure and referred the contact to the NHTSA Hotline for assistance. The failure mileage was approximately 40,000.

NHTSA #11686391

The contact owns a 2020 Chevrolet Blazer. The contact stated upon shifting to park(P) and attempting to turn off the vehicle, the message that the transmission was not in park(P) was displayed. The contact stated that the failure recurred several times, and the vehicle responded as needed after several attempts. The dealer was not notified of the failure. The vehicle was not diagnosed or repaired. The manufacturer was notified of the failure, but no assistance was provided. The failure mileage was approximately 38,000.

NHTSA #11667110

My vehicle has been throwing an error code related to the thermostat. The temperature gauge will remain on C resulting in the fan running loudly, the air conditioner not cooling the cabin of the vehicle well, and a message displaying "steering assist is reduced drive with care". When I check the fluid levels everything is fine without issue. I'm VERY frustrated and want to get rid of my Blazer ASAP.

NHTSA #11667096

I am contacting you regarding my 2020 Chevy Blazer with approx $55,580 Miles. the vehicle is experiencing multiple issues consistent with the know thermostat problem reported on many 2020 Blazer, including the P0128 code, cooling fans running at high speed and "steering Assist Reduced" warnings. The Steering wheel has now become hard to turn while driving, creating a serious safety concern for me and my family, I m [XXX] old and yesterday in mother's day) while I was driving on the expressway with my grandchildren in the vehicle, the steering suddenly became very had to turn and I was almost involved in an accident, This situation was extremely alarming and poses a significant safety risk. PLEASE review many complains from owners who have experienced the same dangerous issue involving the "steering assist Reduce- Drive with Care", warning, sudden stiff steering thermostat malfunction, loss of A/C, and overheating symptoms. I urge Chevrolet and the appropriate safety authorities to investigate this issue and take immediate corrective action to avoid loss of human life. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA #11737156

The driver information center suddenly indicated steering assist disabled, temperature gauge drops to below cold, air conditioning blows warm air. This issue has happened several times and is able to be reset by disconnecting/reconnecting the battery or using a scan tool. Temperature sensor is not the cause in my opinion, and I have read that the harness for the temperature sensor also includes the coil wires, which can lead to electrical/rf interference, triggering this issue. I have read about many owners having this same issue, even after temperature sensor and thermostat replacement, at low mileages. This should be recalled and handled by GM, whatever the cause.

NHTSA #11713538

There seems to be a constant problem with the service driver assist error code popping up and check engine light coming on. The ac heating keeps losing temperature. I've looked for support for this issue and it seems to be a common problem for chevy owners. Why isn't there a recall on this.

NHTSA #11706697

A/C quit working, "Caution Power steering assist ....working, temperature gauge reading zero ( far left side of gauge. PF62F Code set. Repair shop says very common. $800 To repair due to removal of plenum and other component including water temp sensor and thermostat while your there. $100+. 63k miles on vehicle.

NHTSA #11733563

2020 Chevy Blazer RS 3.6L V6: having intermittent issues with ‘check engine’ light activating and giving code P0128 - indicating “Coolant Thermostat (Coolant Temperature Below Thermostat Regulating Temperature)”. Symptoms include: - Temp gauge drops to reading “C” (cold), - AC blows warm/hot air, - Dash displays message, “Steering Assist is Reduced, Drive with Care”, - Radiator (electric) fans run full speed. It seems that the computer is interpreting the engine coolant temperature sensor drop as a ‘stuck open’ thermostat, thus the indicated code. However, at the same time it also appears to assume a bad coolant temp sensor, and failsafes to disable the AC and set the radiator fans to max to avoid potential overheating. The problem with this is that this can occur after driving for some period that the engine is suitably warm, then I can pull off the road, disconnect the battery for a few minutes, and everything goes back to normal operation. A broken thermostat would not behave this way. * This happened in Mar 2025 - after disconnecting the battery about 5-6 times over about a 1wk period the code cleared and we were able to pass inspection. The issue did not reoccur until about the same time this year. It has been recurring periodically since. * After reading numerous postings on this issue, with numerous different vehicles that have this engine and computer, I have no faith that the dealership will provide a solution other than charging me to replace the thermostat, and ending up with the same problem a few weeks later.

NHTSA #11731894

Engine showing PO128 code. Steering Assist System reduced power. Engine fan constantly running. Engine temp on dash is stuck on the "C" mark, doesn't move. Thermostat and temp sensor replaced, issue continues. THIS IS A VERY COMMON PROBLEM ON GM VEHICLES WITH THE 3.6L AROUND THE 60,000 MILE MARK. GM NEEDS TO GET IT FIGURED OUT.

NHTSA #11715931

Just took my car to the Chevy dealership today and had them go over the car because I keep getting the message steering assist has been reduced and the fan is constantly running at the highest speed and it also makes it where I can not use the a/c or heat in the car! I don’t know the code off hand but it has something to do with the cam shaft and the thermostat for the antifreeze! From what Chevy told me today it is a $9000 job to tear down the left side of the engine because the camshaft carrier gasket is leaking oil! Which is probably why that code is popping up. Or from what I was told today it could be from the battery which I believe they were trying to shift blame. Either way this camshaft stuff really needs to be investigated!!

NHTSA #11724826

My vehicle lost complete power while I was sitting at red light. The dashboard went completely out and pop back on stating to put the vehicle in park and push the brake to start. After following those instructions the vehicle failed to start and I left disability until OnStar notified MPD to assist. While waiting for assistance I was almost hit 3 times. When MPD arrived on the scene they were able to push the vehicle out of traffic. After my vehicle arrived at the shop I was told the power failure was caused by the malfunction of the DC/DC CONVERTER Output voltage. I see a bulletin was put out but a recall was my made available. I feel this is a major issue due to the vehicle losing power.

NHTSA #11687550

To whom it may concern, I purchased a new 2020 Chevy Blazer from the dealership five years ago. Since then I have had to replace my battery twice, radiator and now the thermostat all of which have been done at the dealership. The car and all receipts of the repairs are available for inspection if requested. This most recent mechanical issue with the thermostat included the following; fans blowing on high, no AC, check engine light, steering assist reduced message, and temp gauge on C. The car was immediately (same day) taken to the dealership for investigation. Upon inspecting the car the mechanic found the thermostat sticking open and indicated that it would need to be replaced as it was unsafe to drive. A total cost of $1400. It seemed odd that my car is only 5 years old with 75k miles and needing to have the thermostat replaced so I started researching this issue further. I found several complaints on the www.chevyblazer.org forum from other 2020 Chevy Blazer owners with the same mechanical issue. There is one comment on the forum from a mechanic stating that this issue is caused by a faulty wire harness and will continue to cause similar issues until the wiring is fixed. You can find those comments in the forum on www.chevyblazer.org This continues to be an ongoing issue with this make and model of Blazer with no consistent fix from the dealer. I believe my previous battery and radiator issues are all related. I am reaching out to you for assistance and/or guidance to help get this mechanical issue reported as a recall by the dealer and properly fixed at dealer cost. I am happy to provide any additional support you may need to research this further. Thank you in advance.

NHTSA #11657503

I am experiencing the well known "shift to park message" while the shifter is in park. I cannot turn the vehicle off and I am worried the battery will die. This is a well documented issue with this vehicle, and several other models outlined in TSB 19-NA-206, for years and yet they refuse to issue a recall to repair the faulty design or component . I have reached out to them via email, but no action has been taken, see email below. ------------------------------------------------------------------------------------- GM Customer Care, I am writing to request assistance regarding an issue with my 2020 Chevy Blazer VIN# [XXX] . This is my fourth new GM vehicle, and while it is currently outside the 36-month warranty period, the vehicle has only 18,800 miles on it. Recently, the vehicle began displaying a persistent "Shift to Park" message on the Driver Information Center, despite the gearshift being in the Park position. As a result, the vehicle remains in the ON position and cannot be turned off. This is a well-documented issue affecting several GM models, including the Blazer, Acadia, Malibu, Traverse, and Volt. For reference, please see TSB 19-NA-206 attached. Repair costs for this issue appear to vary widely, sometimes exceeding $1,000 depending on location and dealership. Given that this appears to be a known design or component issue, I do not believe this should be an out-of-pocket expense for the customer. As a long-time GM customer, I respectfully request that GM cover the cost of this repair. I am disappointed that there has been no proactive recall or service campaign, especially considering the volume of customer complaints reported online. Thank you for your time and attention. I look forward to your response and hope GM will stand behind its products in this matter. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA #11672407

In March 2025 a Steering assist reduced warning came on briefly. Over the next several weeks intermittent. April 2025 Engine warning light came on. 4-14-25 Went to ToddWenzel Chevrolet for diagnosis to be told the Thermostat needs to be changed and due to a small amount of crystallization on the radiator that as well. I had just had oil changed and fluid levels topped off that morning at Parkway express who did not identify concerns. 4-15-25 brought to Parker Brake who diagnosed and identified there was a glitch that prompted the warning and they can tell that fired when not driving, temp 125Degrees. "it may have been parked cooling down". They noted not need for additional service. Thermostat fine and no evidence of radiator leak. They cleared codes/engine warning. After about a week experiencing intermittent assist reduced warning again. I am understanding that this is a known problem w/ these Blazers and changing thermostat for many does not work. Where does this leave me? GM needs to help with the cost and figuring this out. I am concerned about sudden failure of something while driving that could be unsafe for myself/others.

NHTSA #11657766

On Saturday, March 8, 2025 I was crossing a busy intersection when my car shut off completely and accelerated into oncoming traffic almost causing a collision or fatality. My brakes locked and steering wheel locked. I had to put the emergency brake on in order for the car to come to a stop. We got out of the car in the middle of the street and ran for safety. Scariest experience I’ve ever been in especially with my family in the car!!

NHTSA #11647514

This is what came up on my screen.Steering wheel assist reduced.Drive with care. My hot and cold gauge drop to C and stayed there for about 4 days and my a/c was blowing out hot air. I was told a lot of these Suvs have done this.

NHTSA #11741925

Vehicle thermostat would read cold while operating and the AC was not working. A message would populate in the dash stating "steering assist is reduced drive with care." Multiple forums stated it was a thermostat issue or temperature sensor. Also attempted to disconnect the battery for several minutes which would in turn clear the message and all would be working fine. This has been done multiple times and is at random when the message and AC stop working

NHTSA #11691268

Shift to park message began appearing even after the shifter knob was in park. I cannot turn the vehicle off and it rolled backwards due to the vehicle not recognizing it was in park. This has now cost $700 to repair when its been a known issue with these vehicles for over 6 years and yet they refuse to issue a recall. This is dangerous and disgusting practice for a vehicle manufacturer to avoid keeping their customers safe.

NHTSA #11669125

Engine temp gauge stops working causing the air to stop working and the cooling fan to rev to highest rpm. Also a warning that the steering assist is reduced. Eng check light comes on with a code P0208. This a known problem with an extended service # (N242484760) but only if your vin is listed. All vehicles with this problem should be covered

NHTSA #11740390

The contact owns a 2020 Chevrolet Blazer. The contact stated that while driving at an undisclosed speed, the check engine warning light illuminated. The vehicle was taken to an independent mechanic, where it was diagnosed with VVT sensor failure. The sensors were replaced; however, the failure recurred. The vehicle was taken back to the mechanic, where a solenoid was replaced. The vehicle was repaired. The contact was informed that if the failure recurred, there might be an internal engine failure. The dealer was not contacted. The manufacturer was notified of the failure and referred the contact to the NHTSA Hotline to report the failure. The failure mileage was approximately 70,000.

NHTSA #11718743

This vehicle is currently on its third radiator since it was purchased, 4 years ago. That’s almost 1 radiator per year. The vehicle also has transmission issues on the highway. The dealer replaced the torque converter but vehicle is still hesitant and bucking on the highway. This vehicle only has 64,000 KM and would cost thousands in repairs if it wasn’t under warranty.

NHTSA #11586014

Vehicle: 2020 Chevrolet Blazer Issue: “Shift to Park” malfunction Description: The vehicle repeatedly displays a “Shift to Park” warning message even when the gear selector is fully placed in Park. Because of this issue, the vehicle does not always shut off properly and may continue running electrical systems after the engine is turned off. Symptoms include: * Warning message stating “Shift to Park” * Vehicle not recognizing that it is in Park * Difficulty shutting vehicle off completely * Doors/horn behavior acting abnormally after exiting vehicle * Concern about battery drain and vehicle safety The issue occurs intermittently but has become more frequent over time. The shifter often must be moved multiple times before the warning clears. This appears to be a widespread issue affecting many GM vehicles and may involve a defective shifter assembly or park switch component. I am concerned this defect could: * cause unexpected battery failure, * prevent the vehicle from shutting down properly, * create a safety risk if the vehicle does not correctly recognize Park status

NHTSA #11738429

Shift to park issue. Vehicle shifts into park but does not register as such. Therefore, the vehicle keeps running and will not turn off or allow you to exist the vehicle. This is already a know issue with certain GM vehicles as is evident by a recall and Service Bulletins. However, none of those include the 2020 Chevy Blazer.

NHTSA #11695572

When I try to park the car, it says shift to park. Sometimes I can’t get the car to go into park to exit the vehicle or other times. I’ve shut the door and it has stayed on with the accessories because it won’t shut off

NHTSA #11693643

Engine temp gauge stops working causing the air to stop working and the cooling fan to rev to highest rpm. Also a warning that the steering assist is reduced. Eng check light comes on with a code P0208. This a known problem with an extended service # (N242484760) but only if your vin is listed. All vehicles with this problem should be covered. This seem to be a common problem, as my co-worker is having the same issue. This should be a recall as the steering is affected.

NHTSA #11743407

The temperature gauge does not work, it stays at cold. The heater does not work unless the car is moving. AC does not blow cold air at all. I get a message that says “steering assist is reduced. Drive with care”. There are a lot of people online with the same complaints on these vehicles

NHTSA #11740247

Message pops up saying steering assist is reduced please drive with care. Then the car fan runs all the time on high and the cars temp gauge is running all the way on cool.

NHTSA #11587977

Action required steering assist reduced and coolant temperature at 0. Air con blowing hot and check engine light on. The vehicle became hard to handle and keep in my lane on the interstate at high speeds. The problem has persisted. It has not been recitfied. I am not driving the car to avoid damage and danger. I bought the blazer on 1/6/26. The lights and issues began 8 days later. Dealership will not help me. 2020 Blazer RS AWD bought from Morgan city Toyota Louisiana

NHTSA #11711479

COMMON ISSUE, The steering assist is reduced and temp gauge is stuck on C. This either a thermostat or temp sensor issue.

NHTSA #11651005

Vehicle keeps throwing “steering assistance reduced please drive with care” message. It causes my car fan to constantly run. It also causes the coolant gauge to not work the needle drops below that cool like it’s not on and then the car won’t blow cold air from the vents. This message tells me that something could be wrong with the steering which puts my safety at risk. This issue has been happening to me on and off for months now and there are multiple complaints of multiple Chevy owners having the same problem this issue needs to be addressed.

NHTSA #11621426

At around 55,000 miles my Blazer began to show error codes for “Steering Assist Reduced” and “ESC”. After 60,000 it began to intermittently populate the Check Engine Light paired with the "Steering Assist Reduced" message. Then, the engine fan would turn on high, auto-start when breaking would disable, and the steering would become more stiff. Finally, I was able to get a scan on the code and found out that it was my thermostat. After taking it to my local Chevy dealer I was quoted $1100 to repair. When I called my local mechanic I was told they could fix it for cheaper, but they were unable to find an OEM thermostat in stock which usually means there's a widespread issue with that part. Upon further research, I've found a plethora of complaints online where others with Chevy vehicles are experiencing the same issue. This causes: -Greater fuel consumption -Risk for the engine to overheat -Stiffened steering which could cause accidents

NHTSA #11642269

The contact owns a 2020 Chevrolet Blazer. The contact stated that the transmission was slipping while driving in the lower gears. The contact stated that the message “Reduced Steering - Drive with Caution” was displayed. The vehicle was taken to the dealer but was not diagnosed or repaired. The contact stated that the failure persisted, and the vehicle became inoperable. The manufacturer was informed of the failure and opened a case. The failure mileage was approximately 50,000.

NHTSA #11662076

My shift to park comes on although the vehicle is parked My steering is reduced came on today this is a problem in mutiple forms in regards to chevy blazers

NHTSA #11609998

Engine temp gauge bottoms out because the thermostat is stuck open, causing the air to stop working. Also a warning that the steering assist is reduced. Eng check light comes on with a code P0208. This a known problem with an extended service # (N242484760) but only if your vin is listed. All vehicles with this problem should be covered

NHTSA #11742353

Thermostat is faulty at 55k miles. Purchased 2020 Blazer RS, certified used from Chevy in October 2023. Less than 1 yr later, thermostat is stuck on cold, no ax or heat, drivers assist reduced notice. Same issues as previous documented complaints. The frustration is why this known issue is not covered under warranty or recall! I just had my 50k maintenance service done while this issue was occurring- service told me “well we cleared the codes” , 2 days later check engine is on, temp stuck on cold, fan is over worked and no a/c or heat- and driver assist turns off. The safety issues around causing more engine damage by improper cooling and reduction of driving assistance. Additionally, parking issue with vehicle not recognizing it’s in park and having to wiggle or jam the shifter- car drains battery and won’t lock until resolved. Car is took expensive to have a $1200 replacement not covered under warranty!

NHTSA #11620241

Issues first appeared recorded on 3/9/2026, while odometer read 49,663 miles. Check engine light was caused by error codes P0128 and P01F0. This causes the following issues: * Check engine light to appear on the dashboard. * Engine temperature gauges to be unreliable at times or completely non functional at others, as it will constantly read the engine temperature "Cold". * Air conditioning unit to become unreliable at times or completely non functional at others, and only blow hot air. * Radiator fan will be stuck running at max speed despite current engine temperature. * A "Reduced Steering Assist" message will periodically appear on the dashboard. * A "Service ESC" message will periodically appear on the dashboard. * Remote start will becomes non functional. Car was taken to a license Chevrolet dealership and had full thermostat housing and thermostat sensors replaced. Dealership confirmed all replaced parts are working correctly and as intended. After picking up the vehicle from the dealership, and driving car for roughly 30 miles, the check engine light appeared on the dashboard again causing all previous issues to return. Several other Chevy Blazer 2020 owners have complained of the same issue online, and in forums such as: [XXX] . INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA #11729613

Where do I start. Spring of 2024 I believe, less than 55,000 miles, my transmission went out. No warning. I just went out to my vehicle to go to work and when I put it into reverse, my vehicle make a awful noise, jerked forward almost going into my garage door, then wouldn't move.. I put it back in park, tried to put into reverse again and it wouldn't go. It was stuck in park. Had to get it towed to the dealership where they advised me the transmission went out. It was covered under the drivetrain warranty, but the GM warranty doesn't cover rental. It took almost 4 weeks for GM to approve for a new transmission due to parts being on back order to rebuild my transmission. Several months later, I was driving down the road when the ESC light and then it said "shift to neutral & press start" and I lost power. I coasted into a parking lot, got it fired up, but had no air conditioning (of course it was summer). Took it to the dealer and they said my radiator and A/C Compressor had to be replaced. Luckily my extended warranty covered the $5000 repair. Now 4 months later I got "steering assist reduced, drive with care" with codes. Took to shop and the codes basically was the temp was to low, but the shop couldn't find anything wrong. Cleared the codes and so far so good, but now my ESC light pops on once a week again. I don't even have 60,000 miles on my vehicle.

NHTSA #11705481

I received a check engine light which i took to Bell tire for diagnosis. Here is there diagnosis Comments: The P01F0 code on a 2020 Chevy Blazer means the engine coolant temperature is below the normal operating range, often due to a stuck-open thermostat (or both thermostats in models with dual units), a faulty Engine Coolant Temperature (ECT) sensor, or low coolant, leading to poor fuel economy and potential wear; fixing it usually involves replacing the thermostat(s) or sensor after checking coolant levels and wiring. After that i took the vehicle to GM Dealership. Even though this is a know issue with many vehicles from same year, i was told that my VIN is not part of recall and dealership ended up charging me 600+ to fix the issue. I am reaching out to seek help as i had exact same problem but GM is not covering the repairs because my VIN is not in the recall. How is that possible?

NHTSA #11715555

To Whom It May Concern, I am writing to formally file a complaint regarding ongoing and persistent issues with my 2020 Chevrolet Blazer. The vehicle has exhibited repeated problems that I believe may indicate a broader safety or mechanical defect, and I am requesting that the NHTSA investigate these concerns further. Since purchasing the vehicle, I have experienced the check engine light turning on and off repeatedly, without consistent resolution. The following issues have occurred over time, all seemingly related to the engine or control systems: Engine Cooling System Failure: The first major issue involved the engine cooling system. This caused the vehicle to overheat and required service. I was concerned about the potential for engine damage or fire risk due to excessive heat. Variable Valve Timing (VVT) System Malfunction: Shortly after the cooling system issue, the vehicle began experiencing problems with the variable valve timing system. This not only affected performance and fuel efficiency but also caused the check engine light to illuminate again. Steering Control Assist Sensor Warnings: Most recently, the steering control assist sensor has started to malfunction, with warnings frequently popping up on the dashboard. This has impacted steering feel and raises serious safety concerns. Despite multiple service appointments and repairs, these problems persist or reappear. This cycle of temporary fixes without a lasting resolution is both frustrating and concerning from a safety standpoint. I am requesting that the NHTSA look into whether these recurring engine and control system issues are part of a known defect or recall-worthy problem affecting the 2020 Chevy Blazer. Thank you for your attention to this matter.

NHTSA #11660419

Warning message indicating steering assist system reduced, engine fan running non-stop, AC blowing hot air, temperature gauge not registering/stuck on cold. Faulty engine temperature sensor and thermostat.

NHTSA #11693039

The contact owns a 2020 Chevrolet Blazer. The contact stated while driving approximately 45 MPH, the instrument cluster went black, and the vehicle stalled. The contact stated that there was no warning light illuminated or an audible chime heard. The contact stated that several attempts were needed to restart the vehicle. The vehicle was restarted, and the message "Vehicle in Transport Mode" was displayed. The contact stated that the failure was intermittent but reoccurred. The contact stated that the vehicle was not taken to a dealer or independent mechanic to be diagnosed or repaired. The manufacturer was informed of the failure and referred the contact to the NHTSA Hotline for assistance. The failure mileage was approximately 92,000.

NHTSA #11667252

P0128 code- Assisted steering fault Check engine light Ac blowing cold Temp gauge flat lined Need to replace temp sensor and thermostat. Others with this issue have reported steering can completely lock up, which could cause serious accidents which could result in fatalities.

NHTSA #11625728

2020 Chevy Blazer - Shift to Park while Gear is already in Park: While putting the gear in park, the warning chime to shift it into park is initiated. It has happened 3 to 4 times in the past three days. I took the vehicle to the Local Chevy Dealership. The Service Team/Dept. diagnosed that the Transmission Shifter Unit Assembly must be replaced. The 2019 Chevy Blazer had these issues which prompted a TSB/Recall however it wasn't extended to the 2020-year models and Chevy Dealership refused to include it as a warranted repair which just passed 44,000 miles. This is a safety issue, and it should be replaced without additional cost to customer as this issue was already identified as a safety concern in 2019, however Chevy does not want to identify the issue as a covered repair per the manufactures warranty.

NHTSA #11616457

The check engine light came on with a warning that said "Steering assist reduced drive with care". The temperature gauge went to cold and the air condition quit working.

NHTSA #11736372

My car will be running fine but the lights on the AC panel wont work. My car will stop and shut down while driving. Ive taken it in for service and they told me my battery cabels were lose. The second time it happened I got a notification of low battery level and it shut off and will not start. I just replace the battery 2 years ago. The service department tested my battery and said it was fine

NHTSA #11735381

1) Part that failed per General Motors Chevrolet dealer was the Thermostat along with Coolant Sensor. 2) I was getting warning notices on dash board screen stating (Reduced steering assist) I was also getting a ESC warning 3) Problem has been repaired at GM dealer 4) Parts were replaced by GM dealer/service center 5) ESC warning light that came on for a short time after motor stopped for auto stop / start and then restarted. If auto stop / start was turned off ESC warning did not come on. Reduced steering assist warning would come on but then go off. Finally the service engine light came on and stayed on. 6) GM Service stated Code for engine light was P01F0. Autozone read a P0128 code. 7) From investigating online this seems to be a very common problem with the 2019 and 2020 Chevrolet Blazer with the 6 cylinder engine. Note: I believe this should be a warranty repair due to the fact that 1) This is a known issue with the 2020 Blazer and known poor design 2) The warning about reduced steering assist and 3) ESC warning

NHTSA #11709700

Accident going about 50 mph and no airbags deployed

Reportado presuntamente: 1 lesión (según lo reportado a NHTSA). NHTSA #11696935

I backed my vehicle out of the garage and put it in park and stepped out of the Driver's door. I was going to put my son in his car seat in the rear seat when the vehicle started moving backwards and the opened driver's door knocked us down. I was able to push my son out of the way, but the vehicle continued and the front left tire rolled over both of my legs. The vehicle continued in reverse along the driveway, struck a trash container and went up the incline at the main road. It crossed a busy two lane road and into my neighbors yard. The vehicle came to a stop about 10 feet from our neighbor's house without striking anything else. We purchased this car used with just under 300 mile on it. During the time that we've owned it, it has randomly flashed a "Shift to Park" warning lamp on the dash when I shift it to park and turn it off. It has never done what happened to me today. A few months ago, my husband and I took the car to the GM dealership to have it checked out before the warranty expired. We told them about the "Shift to Park" warning lamp and that the car was shifting hard while driving it. They kept the car a few days and told us they were unable to find anything wrong with it.

Reportado presuntamente: 1 lesión (según lo reportado a NHTSA). NHTSA #11692355

The contact owns a 2020 Chevrolet Blazer. The contact stated that the front passenger’s seat belt buckle was inoperable. The contact buckle was jammed and failed to properly secure the seat belt in place. The contact stated that while driving and stopped at a red light, the traffic light turned green and the accelerator pedal was depressed; however, the vehicle surged forward unexpectedly while rolling. Additionally, the contact stated that the infotainment system intermittently displayed a blank or distorted screen, became frozen and was unresponsive to the touch commands. The vehicle was not diagnosed or repaired. The manufacturer was not notified of the failures. The approximate failure mileage was 75,000.

NHTSA #11744808

The contact owns a 2020 Chevrolet Blazer. The contact stated that while driving at an undisclosed speed, the steering wheel became inoperable. The contact stated that the steering wheel became difficult to turn with a reduced steering message displayed. The vehicle was taken to the dealer, where it was diagnosed that the thermostat had failed, which caused the steering wheel to fail, and needed to be replaced. The vehicle was not repaired. The manufacturer was made aware of the failure. The approximate failure mileage was 54,000.

NHTSA #11664630

Ongoing Engine and Steering Sensor Issues – 2020 Chevrolet Blazer I am filing a complaint regarding repeated safety and mechanical issues with my 2020 Chevrolet Blazer. The vehicle’s check engine light frequently turns on and off, and I have been informed by technicians that it is related to the thermostat system. This issue negatively affects the vehicle’s performance and reliability. Additionally, the “Steering Assist is Reduced – Drive with Care” warning continues to appear while driving, even when weather and road conditions are normal. This error is reportedly due to a steering control assist sensor, and it raises serious concerns about the safety and handling of the vehicle. The alert causes uncertainty and could potentially impact the power steering functionality, creating a hazardous driving situation. These issues have occurred multiple times despite maintenance, and they appear to be part of a broader pattern of defects affecting other owners of this model year. It is unacceptable for a vehicle this new to have persistent problems that affect both engine operation and steering safety. I urge the NHTSA to investigate these recurring issues with the 2020 Chevy Blazer’s thermostat system and steering assist sensor to determine whether a recall or manufacturer intervention is warranted. Safety should not be compromised due to what seems to be systemic defects. Thank you for your attention to this matter.

NHTSA #11659624

Steering assist reduced warning is on all the time. Fan is on overdrive and thermostat needle on cool all the time. Leaking camshaft actuator solenoids

NHTSA #11677780

The contact owns a 2020 Chevrolet Blazer. The contact stated while driving at approximately 55 MPH and driving up an incline in the road, the check engine warning light had illuminated. The contact stated that the vehicle was shuddering. The contact stated that the failure only occurred while driving uphill. The contact had only recently taken the vehicle to a local dealer because the check engine warning light was illuminated. The vehicle was diagnosed, and the dealer determined that the thermostat and the engine control sensor needed to be replaced. The vehicle was repaired. The contact stated that approximately 1,800 miles after the first repair, the check engine warning was illuminated again. The vehicle was taken back to the same dealer. The vehicle was diagnosed, and it was determined that the air flow shutters had been damaged and needed to be replaced. The vehicle was not repaired. The manufacturer was informed of the failure and had referred the contact to the NHTSA Hotline to report the failure. The failure mileage was approximately 97,000.

NHTSA #11661250

Coolant temperature would not read, steering assist malfunctioning, air conditioner intermittent. Wiring harness for sensors loomed together with coil pack wiring interrupting signals.

NHTSA #11655693

Very bad clunnk on driver side when hitting any bump on the road and it's loud.dealer ship sold me the car like that . Electrical issue gauge cluster radio cluster turn signals your first camera anything that works off the instrument cluster of the radio TV screen goes off while I'm driving comes back on hit a bump it comes back on no headlights driving at night time. The dealership sold me the car like this.

NHTSA #11710166

Questions Answered Below: What component or system failed or malfunctioned, and is it available for inspection upon request? The vehicle is at a GM Dealership now and is available for inspection. I have not authorized repairs as of yet. I am being told by the dealership: The ball joint on the control arm on the left side seized snapping the axle shaft - causing the tire to to turn out. The dealership has suggested: Mechanical repair costs $1,850, Plus an additional $2,000 due to wheel well damage caused by the failure. Has the problem been reproduced or confirmed by a dealer or independent service center? I am being told by the dealership: The ball joint on the control arm on the left side seized snapping the axle shaft - causing the tire to to turn out. How was your safety or the safety of others put at risk? Due to my slow speed turning out of the parking lot ~10 mph - the vehicle came to a sudden halt. However, had this occurred while driving any faster - it would have been very dangerous and put myself and others at significant risk. Has the vehicle or component been inspected by the manufacturer, police, insurance representatives or others? It was towed by AAA and has been inspected by the GM Dealership. That is the only inspection thus far. Were there any warning lamps, messages or other symptoms of the problem prior to the failure, and when did they first appear? Earlier in the day while pulling out of a parking spot and turning the wheel to the left I thought I felt some type of resistance then it went away as I started driving. No other symptoms or warning prior to the failure.

NHTSA #11627354

The original issue was that the temperature gauge was pegged on cold and the A/C was inoperative. The vehicle’s fans would run continuously even when the engine was cold. This created a safety concern since the engine’s actual temperature could not be monitored, and loss of A/C affected drivability in hot conditions. The issue appears related to the engine’s coolant temperature sensor or thermostat system, which causes incorrect signals to the temperature gauge and HVAC system. The condition has been reported by multiple owners of the 2020 Chevy Blazer 3.6L. In my case, the malfunction happened suddenly and has been repeatable. There were no prior warning lamps until the issue occurred, at which point the temperature gauge stopped working properly and the air conditioning failed.

NHTSA #11690677

Component/System Involved: The shift-to-park sensor in my 2020 Chevy Blazer is malfunctioning. After shifting into park, the vehicle does not detect it and displays a “Shift to Park” message. The issue is ongoing, and the component is available for inspection if needed. Safety Risk: The vehicle cannot be fully shut off or locked, increasing the risk of battery drain or unintended movement. This poses a safety risk if the vehicle is left in public or on an incline. Inspection History: The vehicle has not been inspected Warning Signs: The “Shift to Park” message appears when trying to turn off the vehicle, despite the gear being in park. This started around Fall 2024 and has occurred regularly since.

NHTSA #11694202

6/12/2024 In Damon Parking lot in Rochester MN. Going less than 10 miles an hr- cars in front of me and behind me looking for a parking spot. Stop and go at times. Went to turn corner to go from one level to the next and my BLAZER took off "like a bullet". No control over accelerated speed- hit outer cement wall and slammed into 2 parked empty SUVS. Could not go any farther. The 2 SUVs slammed into cement wall in front of them. Injuries to both my passenger and myself. I have no idea what happened - it was so fast- I do know I had no control over accelerated rate causing accident. My 2020 Chevy Blazer was totaled- It was inspected by American National Insurance CO. Absolutely no warnings. Police report did not include any witness. Blazer is in the hands of the Insurance Co. Chevy Blazer took off like a bullet - could not stop it!!Police report 24026393 Rochester Police Dept Unable to upload . Checked no police report below so I could continue report.

Reportado presuntamente: 2 lesiones (según lo reportado a NHTSA). NHTSA #11599228

Shift to park issues. Car not reading that it’s in park.

NHTSA #11608438

The contact owns a 2020 Chevrolet Blazer. The contact stated that while attempting to start the vehicle, the brake pedal was depressed, but the pedal was firm, and the contact was unable to start the vehicle. The vehicle was towed to the dealer, where an unknown repair was performed. Additionally, the contact stated that upon taking the vehicle for an oil change, the contact was informed that the service could not be performed because the rear main seal was defective. The vehicle was taken to the dealer, where the contact was informed that the rear main seal was in good condition. The dealer informed the contact that the transmission had failed and that there was a hole in the transmission. The dealer repaired the transmission. The contact related the failure to NHTSA Campaign Number: 20V668000 (Power Train). The manufacturer was notified of the failure, but no assistance was provided. The failure mileage was approximately 80,000.

NHTSA #11702406