Turn Signals Not Working But All the Other Trailer Lights are Working Fine

Question:

i have a 97 ford f150 when i hook up the lights for the trailer the lights work but the turning single will not work what can be the problem

asked by: Crystal D

Expert Reply:

You will be able to find where you lighting issue is by troubleshooting your lighting circuit using a tester like # PTW2993. To start, disconnect the trailer from your vehicle's trailer connector. You will use the tester to check the turn signal coming out of the vehicle.

On a standard 4-pole connector, the right turn signal should be the green wire and the left turn signal should be the yellow wire. If you have a 7-way connector, while looking at the connector, the pin at 3 o'clock is the right turn and the pin at the 9 o'clock location will be the left turn signal. Use the tester with your trucks turn signals on, if you have a signal on both wires, then the issue is not with truck.

Make sure the trailer side connector is free form dirt and other contaminates that could be interfering with the electrical connection. Also make sure the main trailer ground is connected to a clean, bare, and rust free metal surface of the trailer.

Finally, check all the light grounds on the trailer lighting assemblies. Make sure they are connected to a clean metal surface.

I have attached an article on trailer wiring for you to review.

expert reply by: Jared P