Troubleshooting Trailer Lights that Work on 2 Trucks but Not on a Third

Question:

Trailer lights work on a chevy and ford but not 100 on my Toyota brake and turn signals work but no running lights

asked by: Ty

Expert Reply:

I would start by testing the trailer connector at the back of the Toyota and make sure the trailer running lights work at the connector. If not the problem is on the truck. In which case you need to check the correct fuse or inspect the connector and trailer wiring for any damage. Also check the ground location on the truck.

If the problem isn't on the truck then it could be you need stronger gounds on the trailer. It won't be a damaged connector or wiring on the trailer since it works with other trucks but if the Ford and Chevy have higher power output through the trailer connector than the Toyota it could be that the ground connections aren't strong enough for the lower power draw.

If you still can't find the solution let me know what came up while troubleshooting and we'll keep trying.

expert reply by: Charles S