Trailer Wiring Diagram for a Trailer Side 7-Way Connector

Updated 05/01/2012 | Published 04/30/2012

Question:

The wiring from my old pop up trailer has red, white, brown, black, green, and blue wires, as well as a grayground, I think. No yellow. The white and black are larger guage. I just followed the old wiring exactly when installing new 7 pole. Strange light behavior. When changing bulbs, some were corroded and I feel I might have bad bulb connections. Any suggestions?

asked by: Bill C

Expert Reply:

First, you can almost never go by color as there is no real industry standard. You have to go by function when adding a new 7-Way. I have included a picture that shows the trailer side connector and how it should be wired. Ignore the colors, you will need to trace the wiring back to determine the functions.

The corrosion in the bulb sockets and on the bulbs should be cleaned out if at all possible. Corrosion could lead to poor performance down the road.

expert reply by: Michael H