What Color Are the Brake Lights On A 4-Way Flat Plug Of Wishbone Wiring Harness?  

Expert Reply:

The brake signal is run along with the blinker on separate wires. The passenger side is normally green and carries the right turn and brake light. The driver's side is normally yellow and carries the left turn signal and brake. The remaining functions are running/tail lights on the brown wire and the ground which is the white wire. I've attached an article to assist.

A wishbone harness like # A20WB will give you two brown wires so you don't need to run a jump wire from one side of the trailer to the other for your running lights. It separates it at the connection so you can run one brown wire down each side so there is not need to connect anything side to side. I've attached an installation video to assist.