Troubleshooting Trailer Lights Not Working When Brakes Do

Published 02/13/2020

Question:

The trailer lights dont work the turn and the brakes work

asked by: Benjamin

Expert Reply:

Most issues with trailer lights not working stem from issues with the ground connection on the trailer, so this is the first place you should look. You'll want to make sure that the ground is firmly connected to a paint, debris and corrosion free spot on the trailer. You should also check the connectors on both the vehicle and the trailer and make sure that there is no rust or debris on the connections, as well as testing the vehicle 4- or 7-way connector for power going to all of the pins using a circuit tester like the # PTW2993.

If your ground connection is good and your vehicle's 4- or 7-way connector is fully functioning on all of the pins, the issue will be on your trailer wiring. If the 4 or 7-way does not have power on some pins, the issue will be on the vehicle.

If the steps above don't remedy the situation, please let me know and I can let you know what to look at next.

expert reply by: Erik B