Troubleshooting Running lights on 4-Way Connector Not Working

Updated 10/29/2020 | Published 10/28/2020

Question:

I have a 2020 Chev Colorado truck. On the truck bumper I have a factory duel plug, one 7 prong and the other 4 prong flat plug. I recently installed a new duel plug. I have power to all prongs on the 7, but no running light power to the 4 prong. The R/L and brakes work on the 4 plug, but the brown wire doesn’t. Help

asked by: Bill B

Expert Reply:

I recommend first checking the fuse box in your engine bay and checking your trailer park lamps fuse to ensure it is not blown or missing.

If the fuse is there and working correctly I recommend unplugging the wiring harness from the back of your new dual 7-Way and 4-Way connector and verify that none of the contacts inside of the dual connector are damaged causing power to not be transferred through the plug. While there, ensure all wires are tight in the connector and do not have any bare wire showing that could cause an issue.

I attached a trailer wiring article that shows which pins control what on your 7-way and 4-way connector for you.

expert reply by: Samuel C