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:
Accessories and Modifications
Adding non-dealer accessories or making modifications to the vehicle can affect vehicle performance and safety, including such things as airbags, braking, stability, ride and handling, emissions syste ...
Lumbar Adjustment
Manual Lumbar
If available, move the handle forward or rearward to increase or decrease lumbar support.
Power Lumbar
If available, press and hold the front or rear of control to increase or dec ...
Taillamps (Chassis Cab Models)
A. Backup Lamp
B. Stoplamp/Taillamp/Turn Signal Lamp
To replace one of these bulbs:
1. Remove the four screws.
2. Lift the lens off the lamp assembly.
3. Turn the old bulb counterclockwise and ...





