2010 GMC Sierra 1500 Crew Cab Owner's Manual - Page 458

*The fuses for these two circuits are installed in the underhood electrical center, but the wires are not connected. They should be connected by your dealer or a qualified service center. The fuse and wire for the ITBC is factory installed and connected if the vehicle is equipped with an ITBC. The fuse for the battery feed is not required if the vehicle has an auxiliary battery. If the vehicle does not have an auxiliary battery, have your dealer or authorized service center install the required fuse. If charging a remote (non-vehicle) battery, press the Tow/Haul mode button, if equipped, located at the end of the shift lever. This will boost the vehicle system voltage and properly charge the battery. If the trailer is too light for Tow/Haul mode, or the vehicle is not equipped with Tow/Haul, turn on the headlamps as a second way to boost the vehicle system and charge the battery. Camper/Fifth-Wheel Trailer Wiring Package The seven-wire camper harness is located under the front edge of the pickup box on the drivers side of the vehicle, attached to the frame bracket. A connector must be added to the wiring harness which connects to the camper. The harness contains the following camper/trailer circuits: ... Yellow: Left Stop/Turn Signal Dark Green: Right Stop/Turn Signal Brown: Taillamps White: Ground Light Green: Back-up Lamps Red: Battery Feed Dark Blue: Trailer Brake 5-82