2021 Chevrolet Trailblazer Electrical Problems

I am submitting this report regarding my 2021 Chevrolet Trailblazer because it has been experiencing the "Shift to Park" issue described in the GM bulletin 19-NA-206. Even when the vehicle is shifted into Park, it intermittently displays a "Shift to Park" message and does not recognize that the transmission is in Park. This issue has been ongoing and has not resolved despite normal use of the vehicle. It is frustrating to deal with on a regular basis, and it appears to be the same condition addressed by GM in Technical Service Bulletin 19-NA-206 that is available to view on the NHTSA website. I believe the NHTSA should push General Motors to issue a recall for this problem rather than relying on a Technical Service Bulletin. The issue appears to affect many GM vehicles, and owners should not have to bear the burden of repeated repairs or diagnosis for a known defect. I respectfully request that the NHTSA investigate this issue further and require GM to provide a permanent remedy through a recall.

NHTSA ID

11754013

Incident

May 1, 2026

The infotainment system which controls the radio,backup camera, onstart,and other safety components stopped working i took it to a gm certified dealership and it has just been all bad from there. gm has horrible customer service and so does the gm certified shop in michigan city i took my truck in that I only had for 11 months because the infotainment center went of paid for two diagnostic tests they still couldn't] find the issue and now they they're changing me 1,037.76 for a radio which they dont even know if it's going to fix the problem which if it doesn't then I have to pay more money for another diagnostic test and more parts and because I got mad and said I'm paying for a guessing game the dealership told gm that because I had some aftermarket equipment in my vehicle that that caused the issue bullshit the stuff never got plugged into anything at that point the day of my appointment with the audio shop the screen went black with no sound they're all full of shit and didn't want to take responsibility for the widely known issue with the telemedic system

NHTSA ID

11749755

Incident

Jun 25, 2026

My 2021 chevy trailblazer rs is experiencing issues with the infotainment system and the onstar module they have stopped working and I have no backup camera and this issue is a safety concern to me and anyone who rides with me i have contacted both gm and onstar and got nowhere with them after I had a diagnostic test done on 6/18/26 they recommended replacement of the whole system

NHTSA ID

11745155

Incident

Jun 18, 2026

While driving on Thursday, June 4, 2026, the vehicle experienced a sudden and complete failure of the electronic braking/power brake assist system. Simultaneously, multiple safety warnings illuminated on the dashboard display, including a persistent service wrench icon, a traction control warning light, and a lane-keep assist indicator light. Due to the loss of brake assistance, the vehicle was unsafe to operate and had to be towed/driven directly to a licensed dealership for emergency diagnosis. The dealership technicians subsequently inspected the vehicle and reported that the entire electronic braking system had suffered a total failure and is completely non-functional. Despite multiple technical service bulletins and recalls issued for similar vehicle builds regarding electronic brake boost interruptions and mechanical brake vacuum pump failures, I am being forced to pay for these critical safety repairs out of pocket. A sudden loss of braking power poses an immediate crash hazard, and I am filing this report to urge the NHTSA to investigate why this manufacturing defect is not covered under an active safety recall for this specific vehicle configuration.

NHTSA ID

11742380

Incident

Jun 4, 2026

Amplifier lost connection, so speakers won’t work, collision warning won’t sound, and turn signal won’t sound.

NHTSA ID

11742150

Incident

May 27, 2026

Intermittently I will receive a dashboard message reading “shift to park” after I park the vehicle and do shift to park. This is a known issue with this vehicle across several years identified as “a known issue caused by a faulty switch in the shifter assembly failing to detect when the car is in Park”. GM has identified and found a solution to this problem by replacing the entire shifter assembly at the owners own cost. This malfunction has the potential to cause great harm. Potentially the vehicle could roll if the engine/system does not identify that it is in park. This could cause very expensive damages or even take a life. The vehicle also remains in accessory mode which drains the battery and can become even more costly for the owner at no fault of their own.

NHTSA ID

11736470

Incident

Jul 1, 2024

The contact owns a 2021 Chevrolet Trailblazer. The contact stated that while driving approximately 40 MPH, the vehicle stalled. During the failure, several unknown warning lights illuminated, and the vehicle was jump-started. The Auto START/STOP function was disabled for the vehicle to operate properly. The vehicle was inspected by an independent mechanic; however, the failure could not be duplicated. The contact replaced the battery, and the failure was almost resolved. Additionally, while depressing the brake pedal, the vehicle failed to stop as needed. The issue was not diagnosed or repaired. The contact stated that while starting the vehicle, the RPM was abnormally elevated, and the vehicle jerked abnormally while shifting gears. The manufacturer was not notified of the failure. The vehicle was not diagnosed or repaired. The approximate failure mileage was 75,000.

NHTSA ID

11734601

Incident

Jun 26, 2025

Mileage

75,000 mi

When stopped at a red light & the light turns green & I accelerate, the vehicle does not move. It makes a loud noise and jumps. This happens way too many times. There’s also an issue with the brakes, when you press on them, you can hear something grinding, which should not be happening because I bought the car brand new. Also the brakes have always been super squeaky, which is very frustrating because they should not be with a brand new car once again. The engine light goes on and off randomly and doesn’t say anything.

NHTSA ID

11726811

Incident

Feb 1, 2026

After trying to remove rhe key from ignition, it gets stuck and won't come out unless I turn the car on, shift it into drive, wiggle the steering wheel, and try it again. Sometimes it works. Alot of times it take 5-10 min to get it out.

NHTSA ID

11706396

Incident

Jun 10, 2025

The issue is the yellow engine light lit up on the dash of my 2021 Trailblazer in late August of 2025. At the same time, the cluster displayed the message "Engine Power is Reduced". Over the next few weeks my car engine would randomly stall out while I was driving! As you can imagine, this is a very unsafe driving condition. My car stalls and I'm in traffic and have no ability at all to control the vehicle. This happened at least 4 times to me. When I checked the On Board Diagnostic codes on my vehicle the system reported back U060F (Mass Air Flow Sensor). I searched online for this condition with 2021 Trailblazers and found GM Service Bulletin number 22-NA-008, dated March of 2022. This Service Bulletin clearly shows that Chevrolet were well aware of a problem years before it occurred to my vehicle. So, in October I took my car to Bowman Auto Center, explained all of the above to them, and I mentioned the Service Bulletin that I found. Their investigation found that, indeed, the cause of my engine stalling was broken wires to the Mass Air Flow sensor (MAF sensor). Bowman repaired my car and billed me $364.44 as shown on the attached 2-page Repair Order. I tried to make the case with the Bowman Service Department that this should be a warranty repair, and paid by GM. Bowman responded that it was only a Service Bulletin from GM for the issue, and the customer is responsible for payment. I am astonished that repair of this product Design Failure, which results in an unsafe driving condition, would be paid for by the customer! The reason I call it a Design Failure is because NO wiring should break during the life of a vehicle. Engines rock and move, and the Trailblazer design should have compensated for this engine movement by having a sufficient slack loop designed into the wire harness leading to the Mass Air Flow sensor. I filed a case with Chevrolet, number 80982656, but they declined my request for reimbursement $$.

NHTSA ID

11700638

Incident

Aug 27, 2025

There is a faulty sensor on this car that does not allow the car to be properly parked and gives the error message "Shift to park" on the dashboard. You have to turn the car back on and mess with the shifter multiple times to get it to register that it is park. This usually takes about 10 attempts every time you need to park the car. There are other reports regarding this exact issue on this car that further validates that this issue is relevant and needs to be addressed through a recall.

NHTSA ID

11695946

Incident

Jun 30, 2025

While driving, a service warning came on that reads "Service Power Steering" - when that came on, the brakes ceased to work properly and required significant force, causing a big delay in braking. It is not safe to drive due to the limited braking. This mirrors the recall situation for other 2021 Trailblazer models with the interrupted brake sensor.

NHTSA ID

11685359

Incident

Sep 5, 2025

My vehicle displayed a Shift to Park message even though I was already in Park. I could not turn off the engine, I could not lock my car. I had to go back into Drive and then Park mode and wiggle the shifter multiple times to get it to recognize Park and turn off the car. This is now happening almost every time I drive the car. I did an internet search to see how to rectify the problem only to find that this exact issue has plagued GM vehicles for a decade and they still have not chosen to rectify the faulty part. There have been multiple recalls and class action lawsuits for the SHIFT TO PARK fault but not for my vehicle year YET! There are many Trailblazer owners who are experiencing this exact issue (on online forums) and GM so far is refusing to take responsibility and issue a recall to fix the issue for owners and also to stop using this faulty system in their cars. I have reached out to GM about this multiple times the past few weeks and requested they pay for diagnostic and fix the problem because it is a common and known problem with GM vehicles but they want me to pay for it myself and the repair and then they may decide to help out - unacceptable in my opinion. To be honest there needs to be a recall NOW and GM needs to be forced to change the components in all new models to stop this happening in future models going forward. This problem can cause the car battery to drain, it can cause the vehicle to roll away if it’s not recognizing it’s in Park. Thankfully that hasn’t happened to me but others have had this happen. Not being able to shut the engine off or lock my car is a problem. This is a safety issue that needs addressing. I have lots of messages and communication from General Motors which I have attempted to attach the screenshots with the photo below but get an error message on the upload page.

NHTSA ID

11683489

Incident

Aug 12, 2025

The contact owns a 2021 Chevrolet Trailblazer. The contact stated that while stopped at stop light, the vehicle shut off with the check engine warning light illuminated. Due to the failure, the vehicle was towed to a dealer and the transmission was repaired. Despite the repair, the vehicle continued to shut off without warning. One day while driving 60 MPH, the vehicle shut off without warning, and the contact was stranded in the middle of the highway. The vehicle failed to restart after several attempts even with assistance from the Highway Patrol. Due to the failure, the vehicle was towed to the residence and remained at the residence unrepaired. The manufacturer was not notified of the failure. The failure mileage was unknown.

NHTSA ID

11681574

Incident

Nov 1, 2022

I get a shift to park warning after putting the car into park. I’m not able to turn the car off, this has drained the battery and caused safety issues for me and my child

NHTSA ID

11677858

Incident

Aug 1, 2025

Vehicle Diagnostic Summary – Trouble Codes Explained 1. P0562 – System Voltage Low The vehicle’s electrical system is running at low voltage. This could be due to a weak battery, a failing alternator, or poor electrical connections. It may cause various electronic issues and unexpected shutdowns if not fixed. 2. P1005 – Fuel Level Sensor Control Module: Too Many Resets The fuel level sensor module has been reset too many times, likely due to electrical glitches. This may cause the fuel gauge to be inaccurate or unstable. 3. P14C0 / P14CD – Fuel Pump Driver Control Module Signal Error There is a configuration signal error from the fuel pump control module. This could lead to fuel delivery problems, starting issues, or engine stalling if it worsens. 4. U0151 – Lost Communication with Airbag Control Module (SRS) The system lost contact with the airbag diagnostic module. This may affect airbag deployment during a crash, making it a serious safety concern.

NHTSA ID

11676063

Incident

Jul 24, 2025

Put vehicle into park, attempt to turn off car, get message shift to park after the vehicle is already in park. Vehicle keeps message shift to park not allowing car to fully turn off even though car is not started it keeps flashing message shift to park and system such as radio will not turn off as the car thinks it's not in park even though it already is.

NHTSA ID

11673827

Incident

Jun 28, 2025

The contact owns a 2021 Chevrolet Trailblazer. The contact stated that while attempting to remove the key from the ignition, the key remained stuck in the ignition cylinder. The contact had to turn off and restart the vehicle several times to be able to remove the key. The contact stated that the failure occurred intermittently. The vehicle was taken to the dealer who sprayed the ignition cylinder to clean the cylinder; however, the failure persisted. The vehicle was returned to the dealer who diagnosed that the shift lock mechanism failed to recognize that the vehicle was in park(P). The shifter assembly was replaced. The manufacturer was informed of the failure and opened a case. The manufacturer referred the contact to the NHTSA Hotline to report the failure. The failure mileage was approximately 20,000.

NHTSA ID

11665088

Incident

Dec 5, 2024

Mileage

20,000 mi

My vehicle keeps flashing: "Shift to park" when I am in park and then my car is unable to shut off the battery even though I'm in park and our of the vehicle

NHTSA ID

11652696

Incident

Mar 26, 2025

I have had this vehicle at the garage for the 4th time in 2 months for the same issues. It would not start. the fuse box keeps blowing. The starter was replaced and the Alternator was replaced and the fuse box 3 times so far. It is in the auto repair shop now for the same issues. the mechanic has done an inspection and diagnostics and cant find what is wrong. There were no warning lights to warn me of anything. I have spent 4500+ so far in repairs and more to come.

NHTSA ID

11632626

Incident

Nov 22, 2024

2021 Chevy Trailblazer When I go to park my car, there is a constant error of 'Shift to Park'. The car is already in park. I must wiggle the shifting knob, restart my car, or drive around before my car will turn off and recognize that it is in park. My safety is compromised each time I get in the car. If the car cannot recognize it is in park, what happens when it can't recognize it is in drive as I am on the road? Or reverse? Or any gear? My safety is also affected because my car does not realize it is in park, and at times I cannot exit my car. I am highly concerned that the car does not truly know which gear it is in and it compromises not only my safety, but the safety of my family/other passengers, and other drivers on the road. The problem is a known problem and there is an active fix bulletin for the problem. GM cannot get the part in stock - it has been 5 weeks. It affects not only my year, make, and model, but many others too. GM continues to sell the cars with this known safety defect. This defect has been confirmed by the dealership, and GM has sent out a known fix for the issue (TSB PIT5616A). There is also a class action lawsuit for this specific issue with GM. GM's solution to me is to trade in my car for a newer model rather than waiting for the part. In addition, many cars of my year, make, and model require a whole new transmission, but GM will only replace the shifter harness to start with, if and when they receive the part. I was told that the part could take up to six months to receive. For an issue that has been happening since at least 2019, this is unacceptable. The only warning that I receive is when I am trying to shut off my car and it will not shut off due to this error. This has been happening to my car for 2 months, but there seems to be a history of this defect since at least 2019.

NHTSA ID

11628521

Incident

Oct 5, 2024

While driving the car will cut off and on real quick. The headlights will flash on their own. Security systems cuts off and the brakes function messes up.

NHTSA ID

11627856

Incident

Nov 26, 2024

When I place my car in park, a "shift to park" message appears on the dashboard. I am unable to fully turn my car off and the car will ding at me. I have tried driving around the parking lot, pushing the shifter from side to side and into another gear then park again, going forward and backward, but the problem still exists. It started to occur more frequently, until it occurred every time I drove the car. I'm not sure if the car is actually in park, so when I finally get it to turn off, I place the emergency brake on. I can not physically turn the car off when this message appears on the dashboard. I took the vehicle to the service center of the dealer on 11/12/2024. I was told this has been a big problem with GM cars and they have had many cars coming in with the same problem. Currently the part is on backorder, and there is not an ETA as to when it will be available due to high demand for this part.

NHTSA ID

11626823

Incident

Oct 31, 2024

On [XXX] I shifted my 2021 Chevy Trailblazer to park and and was unable to shut off the vehicle. When I shifted it to park it kept displaying an error "Shift to Park" on the dashboard, but the shifter knob was correctly in park. I attempted to press the power button to turn off the car and it wouldnt do anything but beep. I tried multiple times to shift to park to get the car to recognize it was actually in park and turn off the vehicle but I was unable to do so. I was frantic and panicked to find I could not turn off my vehicle as I park on a apartment complex lot. That day I took the car to Henna Chevrolet in Austin Tx for repair. They said the part was on backorder from GM with no ETA. It is now November 1st and there is still no ETA on when I will get the part for my car from GM. This has been going on for 3 weeks now with no end. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA ID

11623129

Incident

Oct 11, 2024

After placing the vehicle in park I get the “shift to park error”. I can’t leave the vehicle, or lock it. It can take any where from 5 to thirty minutes for it to actually read the shift. My car is now not reading my key 80% percent of the time. The vehicle turns off while driving down the road. Saying no “remote detected”. The key has been locked in the Car twice. Which should be impossible. I’ve been stranded outside of my vehicle at night in Atlanta for long periods of time. Trying to get the vehicle to unlock because it is not reading the key.

NHTSA ID

11620584

Incident

Sep 10, 2024