How to Determine Which Wires Connect When Adding Trailer Connector

Updated 09/24/2019 | Published 09/23/2019

Question:

I have 2 green 1 yellow 1 yellow/brown 1 white coming out of trailer I have a 4 way flat 1 green 1 yellow 1 brown 1 white I know the white goes to the white! What does the 2 greens ones go to? What does the yellow one go to? What does the yellow/brown go to?

asked by: David

Expert Reply:

I can help you figure out how to determine how to hook up your connector, though you cannot use colors to determine the functions of trailer wiring (or any wiring) because there is no universal color code, as helpful as that might be.

What you need to do to determine the functions of your wiring is test the wires by function using a charged 12 volt battery and a jumper cable with # 10-1-1 wire, applying 12 volts to each wire which is going to tell you what their functions are; that will allow you to hook up your new connector. I have added a link to a couple help articles on trailer wiring for you to check out which I highly recommend looking through.

expert reply by: Kyle S