How to Wire Trailer with 5 Wires to Connect with Truck with 4-Way Flat Connector

Question:

I have a 4 way flat on truck white yellow brown green and 5 from trailer white yellow green grn/brwn and yellow/brwn. How do i wire it?

asked by: Troy M

Expert Reply:

Your trailer has what is referred to as a wishbone wiring harness which uses a separate running lights wire for each side of the trailer, such as with the Optronics # A35W42B.

The green/brown wire is likely for the right side running lights and the yellow/brown wire is likely for the left side running lights circuit on your trailer. Both of these wires will need to be connected to the running lights circuit on the trailer's 4-Way connector. This will allow it to connect with the standard 4-Way flat on your truck and properly power the trailer's signal lights.

The running lights pin on a trailer side 4-Way is located right next to the female ground pin.

expert reply by: Chris R