How to Wire a 4-Way to a Trailer that Uses Non-Standard Wire Colors

Question:

Dear Sir Please help. I am trying to rewire a small 4 round to a 4 flat. The colors on the small round is black, yellow, red and white. None of your diagrams indicate what colors I should connect the 4 flat to. Please tell me. Thanks

asked by: Ted N

Expert Reply:

The colors on trailer wiring aren't always the same. The best option I can give you would be to determine the functions of each wire so that it can be wired to your new 4-way accordingly.

Chances are one of the wires runs straight to the trailer frame. That would be the ground and would run to the white wire of the 4-way. If there is a wire that runs to both side of the trailer's lights that would be the running lights and would run to the brown wire. If there is a wire that runs to the right side of the trailer that would be the right turn/stop wire and needs the green wire. That leaves the other wire for the yellow of the 4-way.

Otherwise you would need to run a jumper wire from a 12 volt battery to see what each wire activates on the trailer.

expert reply by: Jameson C