Bulletin No.: PIC6643

Service Bulletin

Date: February, 2026

PRELIMINARY INFORMATION
Subject:
Brand:

Cadillac

Front Turn Signal Flash Fast and/or Check Front Turn Signal Message
Model:

XT4

Model Year:

VIN:

from

to

2024

2025

from

Engine:

Transmission:

All

All

to
All

Involved Region or Country

North America

Condition

Customer's may comment that they are intermittently experiencing one or both front turn
signals flashing fast and/or a check front turn signal message.
Condition is more frequent when operated in cold ambient temperatures less than
25 degrees F (-4 degrees C) or colder.

Cause

Internal Headlamp Issue

Correction
To verify the customer's complaint, park the vehicle outside, with ambient temperatures less than 25 degrees F
(-4 degrees C) or colder, for an extended period of time.
If one or both front turn signals flash fast, replace the affected headlamp assembly.
Note: For additional testing, the technician can swap the headlamp assemblies from one side to the other and see if
the fault follows the headlamp assembly.

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

Description

Labor Time

2040510

Front Headlamp
Replacement

Use Standard
Published
Labor Times

Version

1

Modified

02/12/2026 — 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 2026 General Motors. All Rights Reserved.
information.