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.
Tow Ready 4 Pole to 5 Pole Trailer Wiring Adapter