Determining Trailer Wire Function

Updated 07/02/2018 | Published 06/29/2018

Question:

I have a 1990 Circle J two horse trailer. The trailer connector got pulled off and lost. Im trying to install a new one but Ive hit a snag. I dont have a white ground wire. My trailer wires are red, green, brown, blue, black, and yellow. Do you think that the black wire might be the ground. If so, how can I check it? Thanks,

asked by: Michael M

Helpful Expert Reply:

It is impossible to use colors for function on trailer wiring (or any wiring). What you need to do to determine the functions of your wiring is test the wires by function using a charged 12V battery. That's the only way to find out what wires are for what functions. The wire that attaches to the frame with a ring terminal is the ground.

expert reply by: Kyle S