Trailer Wiring Harness
Basic Trailer Wiring
The trailer wiring harness, with a seven-pin connector, is located at the rear of the vehicle and is tied to the vehicle's frame. The harness connector can be plugged into a seven-pin universal heavy-duty trailer connector available through your dealer.
The seven-wire harness contains the following trailer circuits:
• Yellow: Left Stop/Turn Signal
• Dark Green: Right Stop/Turn Signal
• Brown: Taillamps
• Black: Ground
• Light Green: Back-up Lamps
• Red/Black: Battery Feed
• Dark Blue: Trailer Brake*
*The fuse for this circuit is installed in the underhood electrical center, but the wires are not connected.
They should be connected by your dealer or a qualified service center.
If the back-up lamp circuit is not functional, contact your dealer.
If a remote (non-vehicle) battery is being charged, press the Tow/Haul mode switch located on the center console near the climate controls.
This will boost the vehicle system voltage and properly charge the battery. If the trailer is too light for Tow/Haul mode, turn on the headlamps (non-HID only) as a second way to boost the vehicle system and charge the battery.
See also:
Traction Off Light
This light comes on briefly while starting the engine. If it does not, have the
vehicle serviced by your dealer. If the system is working normally, the indicator
light then turns off.
The tract ...
CD Messages
Check Disc: Radios with a single CD player display Check Disc and/or eject the CD if an error occurs.
Optical Error: The disc was inserted upside down.
Disk Read Error: A disc was inserted with an i ...
General Information
For service and parts needs, visit your dealer. You will receive genuine GM parts and GM-trained and supported service people.
Genuine GM parts have one of these marks:
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