Determining Functions of Wires on a Boat Trailer to Install a 4-Way Flat Connector

Question:

I am trying to hard wire mt boat trailer. The boat trailer used to be a 7 blade. i dismantled the head and now trying to install a 4 way flat to those wires. but will not work. Which wires connect to what?

asked by: Isaac

Expert Reply:

Since there is no standard for wire colors and functions you will have to determine the function of each wire on the boat trailer. There are two ways to do this, you can trace each wire back to see where they all terminate. Or you can apply 12 volt power to each wire and see what lights up.

On a Trailer side replacement 4-Way, such as # 18004, the one covered pin is the ground (white is most common). Next to that is running lights (usually brown). Then you have left turn and brake lights (typically yellow). And the last pin is right turn and brake lights (usually green).

expert reply by: Michael H