SB-10045899-9632

GM Bulletin No.: 12188
Date: August 2012

Service Bulletin

SERVICE UPDATE
SUBJECT:

Service Update for Inventory and Customer Vehicles
Starter Motor Short Circuit
Expires with Base Warranty

MODELS:

2013 Chevrolet Avalanche, Silverado
2013 GMC Sierra
Equipped with 4.8L/5.3L V8 Engine (L20, LC9, LMG)

This service update includes vehicles in dealer inventory and customer vehicles that
return to the dealership for any reason. This bulletin will expire at the end of the involved
vehicle's New Vehicle Limited Warranty period.
PURPOSE
This bulletin provides a service procedure to inspect and, if necessary, replace the starter motor
on certain 2013 model year Chevrolet Avalanche and Silverado, and GMC Sierra vehicles,
equipped with a 4.8L (L20) or 5.3L (LC9/LMG) V8 engine. Components within the starter motor
may contact and wear through the wiring insulation, causing a short circuit condition. This could
cause the starter motor to become inoperative and the customer will not be able to start the
engine.
This service procedure should be completed as soon as possible on involved vehicles
currently in dealer inventory and customer vehicles that return to the dealer for any type
of service during the New Vehicle Limited Warranty coverage period.
VEHICLES INVOLVED
All involved vehicles are identified by VIN in the Global Warranty Management System –
Investigate Vehicle History Application. Dealership technicians should always check this site to
confirm vehicle involvement prior to beginning any required inspections and/or repairs. It is
important to routinely use this tool to verify eligibility because not all similar vehicles may be
involved regardless of description or option content.
Additionally, a list of involved vehicles currently in dealer inventory is available on the “Service
Update Bulletin Information” link under the “Service” tab in GM GlobalConnect (US) or attached
to the GlobalConnect message (Canada) used to release this bulletin. Customer vehicles that
Copyright 2012 General Motors. All Rights Reserved.

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August 2012

Bulletin No.: 12188

return for service, for any reason, and are still covered under the vehicle's base warranty should
also be checked for vehicle eligibility.
PART INFORMATION
Parts required to complete this service update are to be obtained from General Motors
Customer Care and Aftersales (GMCC&A). Please refer to your “involved vehicles listing”
before ordering parts. Normal orders should be placed on a DRO = Daily Replenishment Order.
In an emergency situation, parts should be ordered on a CSO = Customer Special Order.
Inventory at this time is limited. Please order only for vehicles that have been inspected and
need to be repaired.
Part Number
12637615

Description
STARTER

Quantity/Vehicle
1 (If Req’d)

SERVICE PROCEDURE
1. Raise and support vehicle. Refer to Lifting and Jacking the Vehicle in SI.
2. Locate the starter motor and starter motor date code information.

2899929

Note: A flash light and mirror are required to view the starter motor date code.
3. Determine if the second digit of the starter motor date code is 8 or 9 (1). The starter motor
date code is an alpha-numeric code that begins with the letter “M.” Look at the next digit to
determine if the starter date code is an 8 or 9 (1).


If the second digit of the starter motor date code is NOT 8 or 9, no further action is
required. Lower the vehicle. Refer to Lifting and Jacking the Vehicle in SI.



If the second digit of the starter motor date code is 8 or 9, remove and replace the starter
motor with a new starter motor. Refer to Starter Replacement (V8) in SI.

4. Lower the vehicle. Refer to Lifting and Jacking the Vehicle in SI.

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August 2012

Bulletin No.: 12188

WARRANTY TRANSACTION INFORMATION
Submit a transaction using the table below.
Labor
Code
V2634
V2635

Description
Inspect Starter Motor – No Further Action Req’d
Inspect & Replace Starter Motor
- Two Wheel Drive Vehicles
- Four Wheel Drive Vehicles

Labor
Time
0.3
0.6
0.9

DEALER PROGRAM RESPONSIBILITY
Whenever a vehicle subject to this service update enters your vehicle inventory, or is in your
facility for service in the future, and the vehicle is still covered under the New Vehicle Limited
Warranty, you must take the steps necessary to be sure the service update correction has been
made before selling or releasing the vehicle.

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 tools,
equipment, 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 dealer for information on whether your vehicle may benefit from the information.

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