Wiring Connections Under Dash of 2003 Dodge Ram 2500 Needed to Install Brake Controller

Question:

03 Dodge 2500 I have the white connector behind the e Brake to connect my brake controller into but there is no power to the blue wire. The black is hot all the time and red wire is hot when appling the brakes. I found a blue wire that looks factory ran from ft to back with a white red stripe wire together. I hooked both up to the battery. Blue wire lights up the trailer brake pin and the white red stripe lights up the positive pin. I have a factory seven pin connector and it looks to be never messed with. Im not sure if I need to tie the blue wire I found into the boys under the dash or not.

asked by: Tim S

Helpful Expert Reply:

The blue wire you found is not supposed to have power to it under the circumstances you tested it. It's supposed to wire to the blue wire of a brake controller like the P2 part # 90885 that you referenced and it carries the of the controller back to the trailer's brakes.

The red wire of the controller attaches to the red wire you mentioned which has voltage when the brakes are applied and the black wire of the controller attaches to the wire that has voltage all the time. The white wire of the controller gets grounded.

expert reply by: Jameson C