PIT6456D Service Bulletin/Repair Instructions

Bulletin No.: PIT6456D
Service Bulletin
Date: February, 2026
PRELIMINARY INFORMATION

Subject:

Brand:
Key Fob Transmitter Buttons Inoperative

Model:
Model Year:

from
VIN:

to
Engine:
Transmission:
from
to
2024
All
All
All
All
BrightDrop
Zevo 400
BrightDrop
Zevo 600
2024
All
All
All
All
Buick
Enclave
2025-2026
All
All
All
All
Buick
Envision
2024-2026
All
All
All
All
Cadillac
CELESTIQ
2025-2026
All
All
All
All
Cadillac
CT5
2024-2026
All
All
All
All
Cadillac
Escalade
2023-2026
All
All
All
All
Cadillac
Escalade

ESV
2023-2026
All
All
All
All
Cadillac
ESCALADE

IQ
2025-2026
All
All
All
All
Cadillac
ESCALADE

IQL
2026
All
All
All
All
Cadillac
OPTIQ
2025-2026
All
All
All
All
Cadillac
LYRIQ
2023-2026
All
All
All
All
Cadillac
VISTIQ
2026
All
All
All
All
Cadillac
XT4
2024-2025
All
All
All
All
Chevrolet
BrightDrop

400
2025-2026
All
All
All
All
Chevrolet
BrightDrop

600
2025-2026
All
All
All
All
Chevrolet
Corvette
2023-2026
All
All
All
All
Chevrolet
Equinox
2025-2026
All
All
All
All
Chevrolet
Colorado
2024-2026
All
All
All
All
Chevrolet
Silverado EV
2024-2026
All
All
All
All
Chevrolet
Suburban
2023-2026
All
All
All
All
Chevrolet
Tahoe
2023-2026
All
All
All
All
Chevrolet
Traverse
2024-2026
All
All
All
All
GMC
Acadia
2024-2026
All
All
All
All
GMC
Hummer EV

Pickup
2024-2026
All
All
All
All
GMC
Hummer EV

SUV
2024-2026
All
All
All
All
GMC
Sierra EV
2024-2026
All
All
All
All
GMC
Terrain
2025-2026
All
All
All
All
Copyright 2026 General Motors. All Rights Reserved.
Page 2

Brand:
February, 2026

Model:
Bulletin No.: PIT6456D
Model Year:

from
VIN:

to
from
to
Engine:
Transmission:
GMC
Yukon
2023-2026
All
All
All
All
GMC
Yukon XL
2023-2026
All
All
All
All
Involved Region or Country
North America
Condition
A customer may comment that one of their key fobs does not function, all fob buttons are

inop.

The fob will work passively for unlocking and allows the vehicle to start as normal when in

the vehicle.

Any additional fobs learned to the vehicle function normally.
Cause
The cause of this condition could be the key fob transmitter being out of synchronization

with the Body Control Module.
Correction

Note: Do not replace Key fobs or the K9 Body Control Module for this concern.

Confirm the customer concern and check the key fob battery by verifying the fob output is above 20% using

the EL-52545 signal strength meter after pressing a fob button ten times in a row.

After verifying the fob battery is good, use GDS2 and navigate to Module Diagnostics > Body Control Module > Data

Display > Keyless Entry Data list and view parameter "Synchronization Counter."

Press any fob button and see if the Synchronization Counter increases by one count for each button press.

If the counter is increasing but the vehicle is not responding to any of the button presses, then the fob is out of sync

with the Body Control Module.

To bring the fob back in sync with the BCM, repeatedly press any fob button on the affected fob until the vehicle

begins to respond to the button presses.

This may take up to 255 fob button presses.

If this procedure does not correct the concern, the bulletin does not apply and follow SI diagnostics.
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
2081378*
Key Fob Synchronization
0.4 Hrs.
*This is a unique Labor Operation for Bulletin use only.
Version
5
Modified
11/24/2025 Created on

01/19/2026 Update to the models and correction sections.

01/29/2026 Update to the correction sections.

02/03/2026 Update to the Condition, Cause, Correction and model sections.

2/20/2026 Update to the Model list
Bulletin No.: PIT6456D
February, 2026
GM bulletins are intended for use by professional technicians, NOT a "do-it-yourselfer". They are written to inform these

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

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

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

information.
Page 3
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Last update on 2026-03-20 / Affiliate links / Images from Amazon Product Advertising API

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