Beginners Guide to RV Wiring

Wiring the 4 pole utility trailer plug

Pin locations for the flat four pole plug

The four pole plug is a simple connection for a boat or utility trailer and is used for lighting only. It is a flat connection with four wires.

4 pole RV plug

Terminal	Wire Color	Function	Location - Truck	Location Trailer
1	White	Ground	uncovered pin	covered pin
2	Brown	Running Lights	1st covered pin	1st uncovered pin
3	Yellow	Left turn/brake light	2nd covered pin	2nd uncovered pin
4	Green	Right turn/brake light	3rd covered pin	3rd uncovered pin