Diagsheet

2021 Chevrolet Trailblazer · symptom sheet

"Shift to Park" or "Service Shifter" warning comes on

  • 32owner reports
  • 33,000median miles
  • 0involved a crash

Newest report Sep 15, 2026 · checked Sep 29, 2026

144 of the 193 complaints on this car are about other. 32 of those describe shift to park warning, which makes it the most reported problem on the 2021 Trailblazer.

No recall on this systemas of Sep 29, 2026
No crash reportedin 32 reports

Tick what matches of 32 reports

12
9
6
1

Shift to park warning on other Trailblazer years

Report counts are for each model year on its own, so a newer car has had less time to collect them.

What this problem usually is

This sheet covers a dash message that says "Shift to Park" or "Service Shifter" when the car is already in Park, or when it's sitting in Drive with the shifter lights glowing. Owners say it won't let them turn the car off, or it flashes up on the highway.

Read the full explainer · Which cars report it most

What got replaced

Few of these reports name the part that was replaced.

Recalls and investigations

No recall on other covers the 2021 model year as of Sep 29, 2026.

NHTSA investigations into other on the Trailblazer

EA12-004opened Jun 11, 2012
Electrical · model years 2006 to 2007

Driver's master power window switch. Closed jun 21, 2013, led to recall 12V-406.

PE12-003opened Feb 9, 2012
Electrical · model years 2006 to 2007

Driver's master power window switch. Closed jun 11, 2012.

None of these investigations covers the 2021 model year.

When it happens

Too few of these reports state a mileage to give a range.

Complaints by the year NHTSA received them: 2023: 1, 2024: 11, 2025: 13, 2026: 71'2311'2413'257'26

Is this a known problem?

The manufacturer has sent NHTSA 1 service bulletin or notice for the 2021 Chevrolet Trailblazer that deal with this problem. Newest first.

Federal rules make a manufacturer send NHTSA a copy of any notice about a defect that goes to more than one dealer or owner. Most of these are service bulletins, the repair instructions manufacturers send to dealers. NHTSA generally leaves safety recall bulletins out of this file, and recalls are listed separately.

What owners wrote

“Shift to park error. I put the car in park but it tell I get a notice to shift the car in park when it’s already in park. Beeps and continues to tell me to shift my car in park when it’s in park. Turn off the car get out and close the door and the notice and beeping continues while the car is off and in park. Been happening since I bought it.”

Filed Sep 29, 2025

“Vehicle has given me a "Shift to Park" message when the sift is all the way up and off at park. You basically has to push hard for the message to go away.”

Filed Sep 28, 2025

“Park to shift error. Vehicle will not turn off while in park, instead gives an alert to "shift to park" even though the vehicle is already in park. Due to faulty park switch or wiring in the shifter assembly”

Filed Sep 18, 2025

“multiple times of getting the warning that i need to "shift into park" when the vehicle is in park. i did have fixed at my local dealer but did have to pay, I know this is been an ongoing issue with many trailblazer . Chevy should look into recalling the failing part.”

Filed Sep 5, 2025

Should you keep driving it?

This page can't tell you that. 0 of 32 reports involved a crash. Owners who file are the ones who had a bad experience, and nobody checks their reports. If the problem affects steering, braking, power or a fire risk, treat it as a safety fault and have it inspected before a long or high-speed drive.

File your own report with NHTSA. Complaint counts are how a problem gets an investigation. How reports land on this sheet.

Guide Taking it to a shop? How to describe this problem so it gets found

Other problems on this car