Troubleshooting Gooseneck Trailer Right Rear Tail Light Not Having Brake Lights Or Turn Signal

Question:

I have a gooseneck, 7 pin trailer. all lights work, except the right rear brake and turn signal. the running lights work on this side, but no brake or turn signal. Whats the issue? thank you!

asked by: MIke D

Expert Reply:

Since only the right rear (passenger side) brake light and turn signal do not work on your gooseneck trailer, that means there is more than likely an issue with that wire.

On trailers the turn signal and brake lights are powered via the same wire. What you will need to do is use a circuit tester like # PTW2993 to test the 7-way connector on your vehicle to make sure it is sending power to that circuit. This will be the 3 o'clock pin as shown in the included diagram.

If you have power, there then you will need to plug in your gooseneck trailer to the truck and test the wires going to the right rear taillight. If there is power to the light but it is not turning on, the light is bad and will need to be replaced.

If no power is making it to the taillight you will need to trace the wire coming from the trailer connector and look for any sections where the wiring may have gotten damaged causing power to be lost. Any damaged sections will need to be replaced with # 16-1-1 and heat shrink butt connectors # DW05744-5.

I included a link to a helpful article on wiring for you to take a look at.