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Service bulletin G-203256

A bulletin is a manufacturer's communication to its dealers, as NHTSA indexes it. The summary is NHTSA's. The document is the manufacturer's: read it at NHTSA. A bulletin is not a recall, and listing a model year does not mean every vehicle of it is concerned.

The communication, as NHTSA indexes it (as of 2026-10-19)
TypeService bulletin
NHTSA id10081063
Published by NHTSA2016-09-28
Manufacturer's numberG-203256
Manufacturer's date2014-10-27
NHTSA componentEQUIPMENT

NHTSA's summary

14262 - SPECIAL COVERAGE. ON SOME HYBRID 2-MODE (HP2) VEHICLES, THE ACCESSORY POWER MODULE (APM) MAY NOT INITIALIZE WHEN THE VEHICLE IS STARTED IN COLD TEMPERATURES AND THE APM IS COLD. ONCE THE APM WARMS UP, IT WILL INITIALIZE AND PERFORM AS DESIGNED. HOWEVER, DURING THE TIME THAT THE APM IS NOT OPERATIONAL, IT COULD RESULT IN A LOSS OF POWER STEERING ASSIST AND THE BATTERY MAY NOT CHARGE. IF THIS CONDITION OCCURS, THE SERVICE POWER STEERING, SERVICE HYBRID SYSTEM, OR SERVICE BATTERY CHARGING SYSTEM MESSAGE WILL APPEAR IN THE DRIVER INFORMATION CENTER, THE MALFUNCTION INDICATOR LAMP AND RED BATTERY TELLTALE MAY ILLUMINATE, AND DTC U1821 AND U182A WILL BE PRESENT. DEALERS ARE TO REPLACE THE APM.

The document

No address for NHTSA's copy can be built for this communication. Ask the dealer for it by the manufacturer's number.

Components

Equipment and accessories

Trouble codes named

U1821, U182A

Vehicles listed
CADILLAC ESCALADE2009, 2010, 2011, 2012, 2013
CHEVROLET SILVERADO 15002009, 2010, 2011, 2012, 2013 (the catalog's model; the bulletin names a series or trim of it)
CHEVROLET TAHOE2008, 2009, 2010, 2011, 2012, 2013
GMC SIERRA 15002009, 2010, 2011, 2012, 2013 (the catalog's model; the bulletin names a series or trim of it)
GMC YUKON2008, 2009, 2010, 2011, 2012, 2013

Listing a model year does not mean every vehicle of it is concerned: the document says which.

Recalls for the same vehicles and component
18V2670002018-04-26. EQUIPMENT
13V5440002015-10-30. EQUIPMENT:OTHER:LABELS
20101892010-06-07. Accessories

A recall listed here may apply to some of the same vehicles. Only the manufacturer can say whether it applies to one vehicle.

Other bulletins for the same vehicles and component
PI0488C2024-05-06. Service bulletin. Diagnostic Information for Transmission.
PI0718B2024-04-29. Service bulletin. Audio System Speaker Rattle, Buzz Noise, Poor Sound
PI0689B2024-04-29. Service bulletin. Tool or Utility Box Sagging, Mis-aligned.
PI0688F2024-04-29. Service bulletin. Poor Voice Quality During Bluetooth Call or OnStar® Personal Call.
PI0688E2024-04-29. Service bulletin. Poor Voice Quality During Bluetooth Call or OnStar® Personal Call.
PI0688D2024-04-29. Service bulletin. Poor Voice Quality During Bluetooth Call or OnStar® Personal Call.
PI0657A2024-04-29. Service bulletin. Liftgate Paint Damage Evident at Lower Outer Edge of Applique.
20-NA-1322024-04-23. Service bulletin. This warranty administration bulletin provides policy information on the requirements for 12V battery testing and warranty replacements.
17-NA-0522024-04-23. Service bulletin. This bulletin updates the position of General Motors on refinishing aluminum wheels. GM has determined that wheel refinishing under warranty will no longer be performed.
PIP5123B2024-04-22. Service bulletin. SES Lamp On With DTC P2270.