How To Determine Wire Function By Color On Trailer Connector

Question:

Hi I purchased the 7 to 5 trailer harness connector from a boat dealership that I purchased the boat from and one of the wires had come off the connector. My question is I’m finding out that the wire colors don’t match up for instance my green wire is connected to the brown connector and my brown is connected to my green connector. Basically, they have my green wire connected to brown and brown connected to green. The wire that came undone was for the blue connector. This is a harness that was already built and I’m trying to find out why it was never connected the proper way and if it matters that the harness was not connected to the desired colors listed on the 7 way connector?

asked by: Dave R

Expert Reply:

It looks like you have a trailer connector like the Pollak Black Plastic trailer connector part # PK12706 in your photo. The color of the wiring on the trailer is not always the best and most accurate way of figuring out their function. It is possible when the trailer was wired that they used nontraditional wiring colors per function.The blue is traditionally the trailer's electric brake output. I recommend to test the wires on your trailer with a jumper wire from a car battery to see which functions activate and then make sure the plug is wired correctly by function and don't worry about the colors because they can vary on the trailer side.

expert reply by: Heather A