Trailer Wiring Has 5-Wires White, Yellow, Green, Yellow/Brown, and Green/Brown

Updated 04/07/2020 | Published 05/18/2013

Products Featured in This Question

Tow Ready 4 Pole to 5 Pole Trailer Wiring Adapter

(260)

$15.72

Question:

4 coming from the vehicle,connecting to 5 on the trailer.matching of colors,white,yellow, brown and green.connecting to white,yellow ,yellow brown,brown,green brown

asked by: Robert

Expert Reply:

On a 4-Way flat trailer wiring harness, white is the ground, brown is running lights, yellow is left turn signal and green is right turn signal.

It sounds like your trailer has a wishbone harness. A wishbone harness splits the running light circuit at the connector so you do not have to run a jumper from one side of the trailer to the other side.

On a wishbone 4-Way connector the white wire is ground, yellow is left turn signal, yellow/brown is left side running lights, green is right turn signal, and green/brown is right side running lights.

If there is a 5th pin then this most likely goes to an electric reverse lockout solenoid, typically found on boat trailers. In order to use it you would need a 4-Way to 5-Way adapter on the vehicle, # 20036. I have linked a video showing a typical installation for you and a link to our FAQ article on wiring.

expert reply by: Michael H

Rob B.

4/6/2020

Only right side is out on my trailer. 4 prong connector. Can I only replace green/ brown wire to right side. How connect to 4 prong harness.

Chris R.

4/7/2020

You could certainly just replace the wiring on the right side of the trailer, but I would first make sure that the trailer wiring is the actual issue. Have you tested the 4-Way on the tow vehicle to make sure the problem isn't coming from the truck? If you are able to verify that the issue is on the trailer - I would try inspecting the wiring before replacing all of it. It might just be a short portion of damaged wiring that needs to be replaced (and not the whole length). Also make sure the light assemblies themselves are good and that they are still securely grounded.

Helpful Links

faq-4-5-way-troubleshooting.aspx