Bulletin No.: 25-NA-249

Service Bulletin

Date: September, 2025

TECHNICAL
Subject:
Brand:

MIL on DIC-DTC P149E Set, Vehicle Equipped with LSY RPO
Model:

Model Year:
from

to

Buick

Envision

2024

2025

Cadillac

XT4

2024

2025

VIN:
from

to

–

—

Engine:

Transmission:

LSY

All

Involved Region or Country

North America

Condition

Some customers may comment on the Malfunction Indicator Lamp being illuminated
and/or the DTC P149E set.

Cause

The cause of the condition may be software anomalies.

Correction

To correct this condition, reflash ECM

Service Procedure
Important: Service agents must comply with all International, Federal, State, Provincial, and/or Local laws
applicable to the activities it performs under this bulletin, including but not limited to handling, deploying,
preparing, classifying, packaging, marking, labeling, and shipping dangerous goods. In the event of a
conflict between the procedures set forth in this bulletin and the laws that apply to your dealership, you
must follow those applicable laws.
Important: This technical service bulletin (TSB) can only be completed by certified repair facilities who have met all
specific training, tool, and equipment requirements pertaining to the vehicle Brand and Model serviced. Repairs must
be performed by a technician who has successfully completed the required training.
Caution: Before downloading the update files, be sure the computer is connected to the internet through a network
cable (hardwired). DO NOT DOWNLOAD or install the files wirelessly. If there is an interruption during programming,
programming failure or control module damage may occur.
• Ensure the programming tool is equipped with the latest software and is securely connected to the data link
connector. If there is an interruption during programming, programming failure or control module damage may
occur.
• Stable battery voltage is critical during programming. Any fluctuation, spiking, over voltage or loss of voltage will
interrupt programming. Install a GM Authorized Programming Support Tool to maintain system voltage. Refer to
www.gmdesolutions.com for further information. If not available, connect a fully charged 12 V jumper or booster
pack disconnected from the AC voltage supply. DO NOT connect a battery charger.
• Follow the on-screen prompts regarding ignition power mode but ensure that anything that drains excessive
power (exterior lights, HVAC blower motor, etc.) is off.
• Please verify that the radio time and date are set correctly before inserting USB drive into vehicle for
programming; otherwise, an error will result.
• Clear DTCs after programming is complete. Clearing powertrain DTCs will set the Inspection/Maintenance (I/M)
system status indicators to NO.
Important: The service technician always needs to verify that the VIN displayed in the TLC left side drop down
menu and the top center window match the VIN plate of the vehicle to be programmed prior to using Service
Programming System 2 (SPS2) for programming or reprogramming a module.

Copyright 2025 General Motors. All Rights Reserved.

Page 2

September, 2025

Bulletin No.: 25-NA-249

• For the TLC application, service technicians need to always ensure that the power mode (ignition) is “ON”
before reading the VIN from the vehicle’s VIN master module and that they do not select a VIN that is already in
the TLC application memory from a previous vehicle.
• If the VIN that shows up in the TLC top center window after correctly reading the VIN from the vehicle does not
match the VIN plate of the vehicle, manually type in the VIN characters from the vehicle VIN plate into the TLC
top center window and use these for programming or reprogramming the subject module with the correct vehicle
VIN and software and/or calibrations.
• The Engine Control Module (ECM) is the master module (for VIP vehicles) that TLC reads to determine the VIN
of the vehicle. If the VIN read from the vehicle by TLC does not match the VIN plate of the vehicle, the ECM
also needs to be reprogrammed with the correct VIN, software and calibrations that match the vehicle’s VIN
plate.
• The Body Control Module (BCM) is the master module (for GEM vehicles) that TLC reads to determine the VIN
of the vehicle. If the VIN read from the vehicle by TLC does not match the VIN plate of the vehicle, the BCM
also needs to be reprogrammed with the correct VIN, software and calibrations that match the vehicle’s VIN
plate.
Caution: Be sure the VIN selected in the drop-down menu (1) is the same as the vehicle connected (2) before
beginning programming.

5743643

Important: If the vehicle VIN DOES NOT match, the message below will be shown

Bulletin No.: 25-NA-249

September, 2025

Page 3

5877000

5644477

Important: Techline Connect screens shown above.
Important: If the same calibration/software warning is noted on the TLC Summary screen, select OK and follow
screen instructions. After a successful programming event, the WCC is located in the Service Programming System
dialogue box of the SPS Summary screen. No further action is required. Refer to the Warranty section of the bulletin.
1. Reprogram the Engine Control Module. Refer to K20 Engine Control Module: Programming and Setup in SI.

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September, 2025

Bulletin No.: 25-NA-249

5644478

Note: The screenshot above is an example of module programming and may not be indicative of the specific module
that is being programmed. Module selection and VIN information have been blacked out.
Important: To avoid warranty transaction rejections, you MUST record the warranty claim code provided on the
Warranty Claim Code (WCC) screen shown above on the job card. Refer to callout 1 above for the location of the
WCC on the screen.
2. Record SPS Warranty Claim Code on job card for warranty transaction submission.

Parts Information
No parts are required for this repair.

Warranty Information
For vehicles repaired under the Powertrain coverage, use the following labor operation. Reference the Applicable
Warranties section of Investigate Vehicle History (IVH) for coverage information.
Labor Operation

Description

Labor Time

4082688*

Reflash ECM

0.3 Hr.

*This is a unique Labor Operation for Bulletin use only.
Important: **To avoid warranty transaction rejections, carefully read and follow the instructions below:

Bulletin No.: 25-NA-249
Labor Operation

September, 2025
Description

Page 5
Labor Time

6125814

• The Warranty Claim Code must be accurately entered in the “Warranty Claim Code” field of the transaction.
• When more than one Warranty Claim Code is generated for a programming event, it is required to document all Warranty
Claim Codes in the “Correction” field on the job card. Dealers must also enter one of the codes in the “Warranty Claim
Code” field of the transaction, otherwise the transaction will reject. It is best practice to enter the FINAL code provided by
SPS2.

Warranty Claim Code Information Retrieval

6125774

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September, 2025

Bulletin No.: 25-NA-249

If the Warranty Claim Code was not recorded on the Job Card, the code can be retrieved in the SPS2 system as
follows:
1. Open TLC on the computer used to program the vehicle.
2. Select and start SPS2.
3. Select Settings (1).
4. Select the Warranty Claim Code tab (2).
The VIN, Warranty Claim Code and Date/Time will be listed on a roster of recent programming events. If the code is
retrievable, dealers should resubmit the transaction making sure to include the code in the SPS Warranty Claim
Code field.
Version

1

Modified

Released September 02, 2025

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.

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