Troubleshooting Tail Light Wiring When Running/Tail Lights Are Not Working

Question:

My 8ft utility trailer has two lights. The left has a brown wire and a yellow wire. The right side has a green wire and a brown wire. 4 wires. My white ground wire is connected to the frame. Turn signals and flasher all work great. I have no tail/running lights. Where is my mistake? Thanks!

asked by: Will J

Helpful Expert Reply:

The brown wire on each side is the running light power and wishbone style harnesses like # A35W42B have the separate running light wires from the connector for an easy run to each side of the trailer. The yellow wire is stop/turn for the left and green is stop/turn for the right. Because you only have the two wires on each side the tail lights will ground to your trailer frame. If there is a separate white wire, that is your ground and most of the time this also needs to be connected to the mounting hardware on the light. Make sure your ground connections are bare metal to metal and free of corrosion or debris.

I've attached a couple of articles to help further.

expert reply by: Jason S