Wiring for Five Trailer Wires to 4-pin Connector on Tow Vehicle

Question:

Hey everyone, Well, this question came up previously, but I’ve managed to provide some photo context this time. I have 5 wires running to my now mangled trailer connector see pic but the replacement connector only has 4 wire slots. What is the method for wiring my 5-wire trailer to this connector? Thanks.

asked by: Chris L

Expert Reply:

It would seem that your tow vehicle has a typical 4 wire connector where white is ground, green is the right turn signal, yellow is left turn signal and brown is running lights. In this configuration the brown wire from the car connects to the brown wire from the trailer.

Also you tell us that your trailer has five wires which are connected to a flat 4-pole connector. It appears that you have a "Wishbone" configuration where two wires for the running lights are merged together for one connection. You will only need the Wesbar Wishbone Wiring Harness # 002402. Personally I would solder these connections and cover in heat shrink tube. Alternatively you could use heat shrink butt connectors that are crimped together.

I have attached a link to a page that further explains trailer wiring and a link for the harness.

expert reply by: Les D