Finding Ground Circuit of 7-Way Wiring With Unknown Wire Colors

Updated 05/14/2018 | Published 05/11/2018

Question:

I have a six wire cable on my trailer. Brown, black, green, red, yellow, blue. I need to rewire to a 7 pin harness to hook up to my pickup. I was not present when the old harness was removed and I now cant identify functions of the wires I believe because Im not realizing which one is my ground. Please help me out

asked by: Tayler

Expert Reply:

None of those wire colors are standard ground wire colors. Typically it's a white wire. The rest of your wires look standard for the most part but since you don't have a white wire you may have to do some testing. You can try using a jumper wire from a 12 volt power source like a battery to apply voltage on each of the circuits to see what taillight functions apply.

The ground will spark when you touch the wires together.

expert reply by: Jameson C