Installing a Voyager Trailer Brake Controller on a 2007 Dodge Ram 2500 with OEM Wiring Harness

Question:

have voyager xp brake controller with no plug. have a 2007dodge 2500 mega cab got the plug from dealer to plug in under dash but the wires are different colors which wires from brake control hook to which wires on plug.

asked by: Dave

Expert Reply:

It is possible that the OEM harness has one of these 2 configurations:

With Green Wire:
Controller Black to White with Red Tracer
Controller Red to Blue with White Tracer
Controller White to Green with Black Tracer
Controller Blue to Blue

W/Out Green Wire:
Controller Black to Red w/ Black Tracer
Controller Red to White w/ Tan Tracer
Controller Black to White
Controller Blue to Blue

The definitive way to determine the functions is to test the factory harness with a circuit tester like # PTW2993 if needed.

When testing the wires, the one that is hot all the time provides 12-volt power to the brake controller and will connect to its black wire. The OEM wire that shows a signal only when the brakes are pressed is input from the brake switch and goes to the controller red wire.

Testing the other 2, ground and output to trailer brakes, can be tricky. If you can use a separate 12 volt battery and apply power to the remaining wires, you can test the 7-Way trailer connector for a signal on the brake output pin. The wire that does send power back will connect to the brake controller blue wire. The remaining wire will be the ground and attach to the controller white wire.

If the OEM harness is labeled, or if Dodge can tell you the color functions, here are the functions of the brake controller wiring:

White = ground
Black = 12 volt power
Red = input from brake switch
Blue = output to trailer brakes