Sierra 2500 2WD V8-6.0L VIN U (2004)
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Trailer Adapter Kit: All Technical Service Bulletins
Electrical - Trailer Brakes Apply With Headlamps ON
Bulletin No.: 02-05-22-004C
Date: April 05, 2005
TECHNICAL
Subject:
Trailer Brakes Applied When Headlights/Park Lamps Are On, Brake Controller Illumination (Modify Brake Controller Wiring Harness)
Models:
2002-2005 Cadillac Escalade, Escalade EXT
1999-2005 Chevrolet Silverado
2000-2005 Chevrolet Suburban, Tahoe
2002-2005 Chevrolet Avalanche
1999-2005 GMC Sierra
2000-2005 GMC Yukon, Yukon XL
2003-2005 HUMMER H2
Supercede:
This bulletin is being revised to add additional model years. Please discard Corporate Bulletin Number 02-05-22-004B (Section 05 - Brakes).
Condition
Some customers may comment that when the headlamps or park lamps are on, the brakes on the trailer are always applied, or that the back lighting for
the trailer brake controller only illuminates when the brakes are applied.
Cause
The cause of this condition may be due to wiring changes within the vehicle electrical system for the 2003 model year.
Correction
Inspect the brake controller wiring harness jumper that is plugged into the vehicle relay block-body. The relay block-body is located under the left side
of the instrument panel near the left kick panel, behind a plastic cover.