Trailer Wiring Harness - GMC 2005 Sierra Denali Owner's Manual

Trailer Wiring Harness

Your pickup is equipped with the eight-wire trailer
towing harness. This harness with a seven-pin universal
heavy-duty trailer connector is attached to a bracket
on the hitch platform.
The Center High-Mounted Stoplamp (CHMSL) wire is
tied next to the trailer wiring harness for use with a
trailer, slide-in camper or cap.
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The eight-wire harness contains the following trailer
circuits:
•
Yellow: Left Stop/Turn Signal
•
Dark Green: Right Stop/Turn Signal
•
Brown: Taillamps
•
White: Ground
•
Light Green: Back-up Lamps
•
Light Blue: Center High-Mounted
Stoplamp (CHMSL)
•
Red: Battery Feed**
•
Dark Blue: Trailer Brake
**If your vehicle is charging a remote (non-vehicle)
battery, turn on the headlamps to boost the vehicle
system voltage and properly charge the battery.