2020 Chevrolet Blazer

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!!

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)

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

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.

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.

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

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?

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

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.

2020 Chevy Blazer thermostat isn't operating correctly.

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.

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.

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.

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

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.

2020 Blazer, 65,000 miles. Temp stuck on cold, A/C blows warm aor and driving assistance off. The radiator fan runs continuously. Check engine light on.

Thermostat/thermostat sensor and complete water outlet system replacement at only 52,377 miles. The defective part was located under the Intake Manifold requiring its removal, excessive labor cost for the repair, and potential future engine issues due to exposed/open head gasket for the repair.

Steering assist reduced message followed by check engine light came on and temperature gauge not moving from cold. Immediately took it to the dealership Hiley Chevrolet in Rockwall, TX. After $250 for diagnostic, failed thermostat is the cause and $1216 repair cost. Known issue that Chevrolet issued special coverage for 2021 Blazers, but none for 2020. My vehicle has a little more than 51,970 miles. Same vehicle just had battery replaced two weeks ago at same dealership and no other issues showed up during diagnostic then.

Thermostat gauge isnt moving along side a message saying "Steering assis is reduced drive with care"

Accident going about 50 mph and no airbags deployed