2019 CHEVROLET BLAZER Complaints

2019 Chevy Blazer. Car would not turn off the electrical components when parked. Put car in park and walked away and there is a warning note that says, "Shift to Park." But the car was in park. Called Chevy and they know about the issue on the 2019-2023 vehicles. They sent me the Technical Service Bulletin. Back in 2020, the car had the shifting harness and button replaced and we just had to have it replaced again because it is a consistent issue with the vehicle. Except this time, the dealer charged us $668.40 to fix it! It is a known issue by the company and THEY sent me the service bulletin to get it fixed. It should have been covered by Chevy, or, at least a recall should be instituted. The power to the car wouldn't shut off. We were able to jump the car to get it started again.

I believe my thermostat is a problem. I keep getting "P012B" "coolant under operating temperature" codes on my obd2 meter. This seems to coincide with "driver assist reduced" on my instrument cluster on my dash board. I researched it and on a forum it sounds to be a very common problem. Someone said to report it on here. I can clear the "p012b" error code with my obd2 and my thermostat instantly becomes responsive however it comes back within 2 days or so.

Faulty thermostat. Check engine light comes on due to thermostat getting stuck open and needing to be replaced. This is terrible for the engine and the environment.

The shift-to-park sensor in my 2019 Chevy Blazer RS is malfunctioning. After shifting into park, the vehicle does not detect that it is in park and displays a “Shift to Park” message. The issue is/has been ongoing and now it is almost impossible to bypass with wiggling the shifter. 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 was taken in to the dealership in November/December 2025 due to MULTIPLE Warning Lights: “Shift to Park”, "Steering Assist", "Stabilink" and the usb-C charging port under the radio screen will stop working all together when this happens as well. This started around September 2025 and has occurred regularly since.

Thermostat Housing Replacement + Dexcool: P0128, thermostat stuck. Was told this can cause engine to overheat.

The thermostat has been sticking, and needs to be replaced after only 30,000 miles.

Was getting a steering assist reduced error code. Auto stop quit functioning and air conditioning stopped cooling. Engine sounded like a jet. P 0128 thermostat error code came up and had to be replaced. I see lots of similar complaints. Cost me $700.

My car lost power twice in the middle of heavy traffic we could have gotten killed .i was told it was a battery I bought a battery it happened again .The car goes totally black and it locks you in the vehicle you can’t get out I had to call for help scared to death

I have replaced the thermostat sensor 3 times because keep getting assist driver assistance disabled throws code p1028 code coolant drops check engine light come on the auto stop quits working

Shift lever to Park Alert on dashboard. Paid to have shift lever replaced on Blazer. Also had same problem on 2018 Malibu..paid myself to have shift lever replaced! I was NEVER NOTIFIED about a Class Action suit. I believe this is a MAJOR PROBLEM on GM vehicle. NEED GM TO HAVE A RECALL!