2021 Chevrolet Trailblazer Problems

What owners report

Complaints on the 2021 Chevrolet Trailblazer cluster around a shift-to-park message that prevents the vehicle from shutting off, intermittent rough or delayed transmission engagement, and repeated brake and electrical warnings. Many reports come in at low mileage (under 20,000), while transmission, turbo and engine complaints tend to appear from roughly 30,000 to 90,000 miles.

1. 1
   Transmission and drivetrain

   Shift to Park message; vehicle won't shut off

   Mentioned in 12 of 60 sampled complaints

   Owners report that after shifting into park the dashboard displays "Shift to Park" or "Vehicle Not in Park" and the vehicle will not power down, sometimes beeping or dinging for many minutes. Several describe cycling the shifter in and out of park, wiggling it, or restarting the engine repeatedly before it recognizes park; a few mention the battery draining when it never does. Complaints say dealers diagnosed a failed shifter or shift-lock switch and replaced the assembly, sometimes more than once, with parts back-ordered in some cases. Reported from roughly 16,000 to 79,000 miles, often within the first few years of ownership and recurring after a prior repair.

   1 related service bulletin

   What to check: With the engine running, shift into park and confirm the vehicle shuts off cleanly and the message does not appear; ask whether the shifter assembly has ever been replaced and whether the repair was covered.

   2 excerpts from owner complaints in NHTSA records

   “The vehicle began to give the error Shift to Park when the vehicle was in park and after the power was shut off. Because of this I cannot safely turn off the vehicle because it cannot recognize it's in park and will run the battery down whenever I use the vehicle. This problem has been previously presented in other models manufactured by GM. I am taking the vehicle in for inspection at a local Chevrolet dealership on 9/24/22 at 8 am. This issue first started around the second week of September this year with one or two errors here and there. …”

   NHTSA complaint #11486048, filed 2022-09

   “When putting the vehicle in park an error displays, SHIFT TO PARK, and the vehicle does not turn off completely and will ding although you’ve put it in PARK. This has been happening for well over a year and the dealership says it’s a known issue but not a recall. There are times it’s taken up to 25 mins that I’ve had to sit in the vehicle to get the vehicle to turn off by wiggling the shifter or just putting it in drive and back into park, hitting the shifter button, etc. …”

   NHTSA complaint #11750520, filed 2026-07
2. 2
   Brakes

   Brakes feel unresponsive or noisy, with warning messages

   Mentioned in 11 of 60 sampled complaints

   Complaints describe the brake pedal needing heavy pressure or going to the floor, grinding and squealing noises, and dashboard alerts such as "Service Stabilitrak" or brake system failure. In some reports the problem appeared within the first few hundred miles; owners say dealers could not duplicate the condition, reset software, or told them the brakes looked fine. One owner reports a loud pop through the speakers when the brake pedal is pressed. Reported across a wide range, from under 200 miles to well past 100,000 miles, with several cases under 8,000 miles.

   Recall 20V588000

   What to check: Ask whether the electronic brake boost sensor recall (20V588000) was completed, test the pedal for firmness and noise on a test drive, and have any stored brake or Stabilitrak codes read.

   2 excerpts from owner complaints in NHTSA records

   “Two times I have heard a loud pop noise coming through my stereo speakers. I noticed it when applying the brakes. I went on a Trailblazer forum and a few others had reported the same thing. I heard the pop today when I was pulling into a parking spot and applying the brakes.”

   NHTSA complaint #11403605, filed 2021-03, 2,000 miles

   “I was driving my brand new 2021 Trailblazer (only 160 miles) and stepped on the brake to stop at the end of a street. Suddenly, I got alerts that my brake system had failed and right after that, another one, saying that the power steering needed to be serviced. At that point, it required much more pressure on the brake to stop, and the brakes didn't seem very responsive. Later I shut off the engine, and when I started it again, the check engine light was still on, but I think the brakes were working again. …”

   NHTSA complaint #11415441, filed 2021-05, 160 miles
3. 3
   Engine

   Turbo and engine power complaints (reduced power, rattle)

   Mentioned in 9 of 60 sampled complaints

   Owners describe a loud clicking or rattling at low speed, a "reduced engine power" message, and a vehicle that will not accelerate normally or goes into limp mode. Complaints say dealers replaced the turbocharger, fuel injectors, or diagnosed variable valve timing and camshaft actuator problems, and in some cases the symptoms returned after repair. A few reports describe coolant intrusion, overheating from a coolant control valve, and a stalling engine that would crank but not start. Usually reported from roughly 40,000 to 90,000 miles, with a few cases around 128,000 miles.

   2 related service bulletins

   What to check: Listen for rattles on a cold start and at low speed, check for a stored P0299 or boost-related code, and ask whether the turbocharger or ignition-related parts have been replaced.

   2 excerpts from owner complaints in NHTSA records

   “Vehicle was taken to dealership feb 2026 for turbo/wastegate repair (p0299). March 22, 2026, vehicle stalled and screen said to shift to neutral and push to start again. Car would crank but not start (sounds like there is no compression). Had vehichle towed two miles to residence and connected to obdii scanner, which showed 6 new codes (p0006, p228c, p0089, p0340, p0365, p0299).”

   NHTSA complaint #11727149, filed 2026-03

   “The Turbo is bad in the car at 90,000 miles. It is a common issue among these, lots of other people have the same issue with the “engine power is reduced” message popping up, per the 2021 Chevrolet TrailBlazer facebook group. There needs to be a recall so they can be fixed. It has happened on mine for the past few months and the dealer said the turbo is bad. The purge pump has already been replaced.”

   NHTSA complaint #11589866, filed 2024-05
4. 4
   Electrical system

   Electrical faults: no-start, fuse box, infotainment outage

   Mentioned in 9 of 60 sampled complaints

   Owners report intermittent no-start conditions with a repeatedly blowing fuse box, starter and alternator replacements, and mechanics unable to find the cause. Others describe the infotainment screen and OnStar module quitting, which also takes out the backup camera, and report being quoted for full system replacement without a confirmed diagnosis. Stuck ignition keys and flickering lights or brief electrical cutouts while driving also appear. Spread from a few thousand miles to over 70,000 miles, with several reports in the first year of ownership.

   4 related service bulletins

   What to check: Test the radio, backup camera and OnStar functions, check that the key releases freely from the ignition when shut off, and ask whether any electrical or infotainment diagnostics have been run.

   2 excerpts from owner complaints in NHTSA records

   “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 complaint #11745155, filed 2026-06

   “My key gets stuck in the ignition almost every time I turn the car off. In order to get it unstuck I have to restart the car, put the car in drive or reverse, put the car back in park and then try to take the key out again. This has to be repeated sometimes as many as 10 times for it to finally release the key. I have read about many other people having this same problem and eventually the key not coming out at all and they've had to have it cut out. …”

   NHTSA complaint #11604275, filed 2024-07
5. 5
   Transmission and drivetrain

   Rough or delayed gear engagement, loss of power

   Mentioned in 6 of 60 sampled complaints

   Owners report the vehicle hesitating or refusing to move after being shifted from park or reverse into drive, sometimes accompanied by a loud noise, a jump, or a stall while accelerating. Complaints mention check engine lights, limp mode limiting speed, and dealers diagnosing transmission control module or solenoid faults, underboost, or a bad turbo. Several owners say the symptoms are intermittent and hard to reproduce at the shop. Mostly reported between about 30,000 and 85,000 miles, sometimes after other drivability repairs.

   2 related service bulletins

   What to check: On a test drive, shift between park, reverse and drive several times on a slight incline and note any delay or clunk; ask whether transmission codes have been stored or any transmission repairs performed.

   2 excerpts from owner complaints in NHTSA records

   “I am reporting a serious safety issue with my 2021 Chevrolet Trailblazer related to transmission failure. The vehicle has approximately 83,000 miles. While driving, the vehicle experiences a sudden loss of power when attempting to accelerate. In some instances, the vehicle has stalled or shut off while I was actively driving, creating a dangerous situation, especially when merging into traffic or driving through intersections. The issue is intermittent but has become more frequent over time. …”

   NHTSA complaint #11734472, filed 2026-04

   “I have had the 2021 Chevy Trailblazer since May 2021, it has been 15 months, not even a year and a half off the lot and i have had wayyyy too many problems. I have has service the stabilitrak stability control system, service the antilock breaking system multiple times within the first 8-10 months. I had to get a part replaced due to that. The dealership had my vehicle literally for a month after i bought it, had an open tak report through Gm due to my engine light coming on. Gm did not know why it was happening. …”

   NHTSA complaint #11481702, filed 2022-08

Buying note. Check the shift-to-park behavior and transmission engagement on a test drive, confirm the brake boost recall was completed, and ask for service records covering shifter, turbo and electrical repairs. A pre-purchase scan for stored codes is worth the cost given how often complaints mention intermittent faults.

Summary written with AI from a sample of 60 NHTSA complaints for this model year (picked at random, with complaints that state a mileage and recent ones taken first), then checked automatically against the source records. Counts refer to that sample. The excerpts come from NHTSA's public complaint records and are unverified; capitalisation is normalised, NHTSA staff notes are removed, and shortened text ends with “…”. Something wrong? Request a correction.