Trailer wiring harness

[Nick H]

I have a new to me 2005 2500 that I need to hook a brake controller to. I found the harness under the dash but can't figure out which wires go where. The truck harness wires are not marked like my 98. I have one blue with a white stripe,white with red stripe, green with black stripe and one light blue. If any one knows I would appreciate the help. Thanks

 

[HBarlow]

That doesn't sound like the correct harness to me. The normal brake controller harness contains a blue wire, which is brake power out to brakes, red, which is brakes applied signal in to the control, and, IIRC, black is 12v always hot, and white is ground.

You can identify the correct wires if that is the correct harness using a simple test lamp. If one of the wires is always hot (will always light the test lamp it is 12v hot. If another will light the test lamp when the brake pedal is pressed down that is the red wire or brake signal in. It will be more difficult to identify the brake signal out.

 

[Hoefler]

There is a plug under the wire bundle that comes through the fire wall. You need the pig tail to plug into it. You can get this from the dealer or after market vendor of trailer wiring parts.