PIC6621 Service Bulletin/Repair Instructions

Bulletin No.: PIC6621
Service Bulletin
Date: October, 2025
PRELIMINARY INFORMATION

Subject:

Brand:
Roll Windows Down / Up Message

Model:
Model Year:

from
Cadillac
LYRIQ
VIN:

to
2023 - 2026
from

All
Engine:
Transmission:
to

All
All
All
Involved Region or Country
North America
Condition
Some customers may intermittently see a message instructing them to roll down then up

one or more windows.

Despite the message, the windows continue to operate normally.
Cause
Engineering is currently investigating.
Correction

Test the 12 volt battery.

Check 12 volt battery cable connections.

If no issues are found, Do Not replace any parts.

Engineering is currently investigating.

In the meantime, please advise customer they may continue to drive the vehicle.

The PI will be updated or replaced with TSB once a determination has been made.
Warranty Information

For vehicles repaired under the Bumper-to-Bumper coverage (Canada Base Warranty coverage), use the following

labor operation. Reference the Applicable Warranties section of Investigate Vehicle History (IVH) for coverage information.

Labor

Operation

*1080778
Description
Labor Time
Check 12V Battery and

cable connections.
0.5 Hr.
*This is a unique Labor Operation for Bulletin use only.
Version
1
Modified
10/3/2025 Created
GM bulletins are intended for use by professional technicians, NOT a "do-it-yourselfer". They are written to inform these

WE SUPPORT VOLUNTARY

technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper

TECHNICIAN

service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions, and know-how to do a job

CERTIFICATION

properly and safely. If a condition is described, DO NOT assume that the bulletin applies to your vehicle, or that your

vehicle will have that condition. See your GM dealer for information on whether your vehicle may beneﬁt from the

Copyright 2025 General Motors. All Rights Reserved.

information.

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