2020 Chevrolet Blazer Complaint Log

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.

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!!

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

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)

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?

2020 Chevy Blazer thermostat isn't operating correctly.

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.

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

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

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

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.

Component/System Involved: The electric power steering system in my 2020 Chevy Blazer is malfunctioning. A warning appears on the dashboard: “Steering Assist is Reduced – Drive with Care.” When this happens, steering becomes very stiff and difficult. The issue is ongoing, and the component is available for inspection if requested. Safety Risk: This creates a serious safety hazard. The sudden loss of steering assist makes it hard to turn the wheel, especially at low speeds or when maneuvering. It puts me and others at risk, especially if it happens in traffic or while turning. Problem Confirmed by Dealer: No, the issue has not yet been inspected or confirmed by a dealer or service center. Inspection History: The vehicle has not been inspected by a dealership, manufacturer, police, or insurance. Warning Signs: The only warning is the “Steering Assist is Reduced – Drive with Care” message, which appears randomly—sometimes at startup, sometimes while driving. The issue began around 10/15/2024 and continues to be an on going issue.

"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.

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

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.

The thermostat failed on a trip locking in 0 temperature reading and steering assist warning. Licensed mechanic repaired on 10/9/25 invoice is available. 67,509 miles. This could risk overheating and destroying the engine and might cause accident. Two other friends have had similar issues, appears to be a safety defect!

Engine light on, power steering assist, air conditioning stop working diagnostic tool read p0128 coolant thermostat

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

While driving an alert came up "adaptive steering limited, drive with care". At the same time, my AC stopped working a d my thermostat dropped to cold and will not move from there. From searching online, this is a common and known issue with Chevy SUVs yet there is no recall or attempt to correct.

Check engine light on, message saying "steering assist reduced drive with care", engine temperature gauge not moving from C, and AC not working. I have taken it in to be fixed 3x, and they have fixed it 2/3 times but the message has come back again. It is a big issue in 2019/2020 blazers according to my research.

Similar to the Bulletin No.: PIP5681C The flex pipe bracket is cracked on my 2020 chevy blazer this causes rattling and whining noises due to the part rubbing against where it was previously connected.

SHIFT TO Park WARNING COMES ON WHEN CAR IS IN PARK, car electrical will not shut off until the shifter is shaken or car is turned back on and shifted into gear and back to park, may take several times

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.

P0128 code for thermostat issue. Fans run after shutting car off. Steering assist reduced message. Check engine light. Chevy knows this is a common issue. This needs to be investigated asap.

2020 Chevrolet Blazer, 19900 miles, lightly driven The radiator seam is leaking coolant, which appears to be a known issue as there are numerous complaints on various websites and forums. The vehicle is now unreliable due to an overheating risk.

The contact owns a 2020 Chevrolet Blazer. The contact stated that while attempting to park the vehicle, the gear shifter was shifted into park. The message “Shift to Park” was displayed while attempting to restart the vehicle. The dealer was contacted. The vehicle was not diagnosed or repaired. The manufacturer was made aware of the failure and referred the contact to the NHTSA Hotline for assistance. The approximate failure mileage was 54,843.

Shifter Assembly and Harness When putting vehicle into "Park" and then shutting off the vehicle a warning message would appear that the car had to be placed into park and a beeper would sound. Never sure if vehicle is actually in park. Have to restart the vehicle, move the parking gear from park, then back into park until message does not appear. This issue was a recall for the 2013-2019 Chevy Blazers, but was not recalled for the 2020 Blazer, although it appears that this is still an issue. Had issue repaired by paying for the replacement of this shifter assembly.

After the vehicle has been put into parked and attempted to shut off, a message displays “Action Required Shift To Park”. Although the vehicle is in parked there is some kind of sensor that is not reading it is in park. Vehicle first started doing this when parked on an incline but frequently happens since the first occurrence. One temporary solution is to shift into different gear or shake the gear shift.

When you shift to park it tells you shift to park and you can't turn the car off.

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.

The contact owns a 2020 Chevrolet Blazer. The contact stated that while his wife was driving 80 MPH, the vehicle failed to accelerate as intended while depressing the accelerator pedal. In addition, the contact stated an abnormal sound could be heard coming from the engine. The vehicle stalled and the contact's wife was unable to move to the side of the road. The message "Shift to neutral and press the start button" was displayed. The police assisted with traffic control while the vehicle was pushed to the side of the road. The vehicle failed to start. The contact stated that prior to the most recent failure, the gear shifter would be stuck in park(P). The contact would move the gear shifter several times to cause it to move. The contact stated that the failure recurred several times, and the vehicle responded as needed after several attempts. After several attempts, the check engine light was illuminated. The vehicle was not diagnosed or repaired. The manufacturer was made aware of the failure and referred the contact to the NHSTA Hotline for assistance. The approximate failure mileage was approximately 40,000.

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.

When I come to a stop, in an attempt to park, I will shift into park but a message will appear on my dash saying to shift to park this prevents me from shutting off the vehicle. The issue is persistent at times, but happens intermittently.

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.

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.

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.

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.

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)