Troubleshooting Right Turn Signal on 5th Wheel Trailer Malfunctioning

Question:

Truck singles all work right and left, when l plug the 5 wheel in ,the left side works, the right side on 5 wheel dose not. Did a continuity check on the plug on all of the leads. All check out,all bulbs are good. Brake lights all work. Running lights all work. Can you help me.

asked by: Nick F

Expert Reply:

It sounds like you have a short on the circuit for the right turn signal on your 5th wheel trailer.

If the 7-Way on your tow vehicle and your 5th wheel look good then you will want to start off by using a Circuit Tester # PTW2992 to test the pin in the 3 o'clock position on your tow vehicle side 7-Way (see attached picture). If you are getting a signal when you use your right turn signal then the problem is on your trailer.

Either way, you want to start off by checking the grounds on the side of your towing setup that is causing the short. Make sure they are secure and connected to a clean, bare metal surface as even some paint can cause issues. You will then want to look for any wiring along that circuit that is bent, corroded, exposed, or damaged. Replacing it with some 16 Gauge Wire # 16-1-1 and Butt Connectors # DW05744-5 should fix your problem.

If you are still having issues after doing this, or if you check all of your wiring and cannot find a problem, then it would be best to take your setup to a local shop and have them physically inspect it for you.

expert reply by: Jon G