Sierra 1500 4WD V8-5.3L VIN B (2005)
Engine Control Module: All Technical Service Bulletins
Engine Controls - Battery Lamp ON After PCM Replacement
Bulletin No.: 05-08-49-010A
Date: April 18, 2005
INFORMATION
Subject:
Information on ReSetting the Battery Light If It Remains Illuminated After PCM Replacement
Models:
2005 Cadillac Escalade
2005 Chevrolet Avalanche, Silverado 1500 Series, Suburban, Tahoe
2005 GMC Denali, Sierra 1500 Series, Sierra Denali, Yukon XL
with Regulated Voltage Control (RVC) Module
Supercede:
This bulletin is being revised to include additional information on the IPC/RVC module. Please discard Corporate Bulletin Number 05-08-49-010
(Section 08 - Body and Accessories).
After successfully reprogramming a service Powertrain Control Module (PCM) with Regulated Voltage Control (RVC) module, the technician may find
the battery light is illuminated even after multiple ignition cycles.
The instrument panel cluster (IPC) receives a battery light request from the RVC module, not the PCM. The PCM for the above-mentioned vehicles for
model year 2005 may contain old PCM software that sends a Class2 message (Alternator Lamp) to the IPC. If the IPC receives a message, the IPC learns
that the PCM sent the message and expects the PCM to always send the message. If the IPC does not receive the message from the PCM, the battery light
will illuminate. Once the service PCM is programmed with latest model year 2005 software, the PCM will never send this Class2 message again.
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Remove the IPC/DIC fuse from the Underhood Fuse Block for approximately 30 seconds. Refer to the diagram for the location of the fuse.
^
Disconnect the Positive Battery terminal for approximately 30 seconds and then reconnect. If this method is used, make sure to save all preset
