Troubleshooting Wiring Harness for 2017 Nissan Titan with Trailer Lights Not Working

Question:

I purchased the CURT 55384 Replacement Vehicle-Side Custom USCAR 4-Pin Trailer Wiring Harness for my 2017 nissan titan and my trailer lights are not working. I already had the relays in the truck. It worked on a new boat trailer, but not the one I have. Also, the boat trailer worked on my jeep. Just will not work on my truck. Please help

asked by: Loretta G

Expert Reply:

It sounds like the Curt # C55384 is working properly with other trailers just not one specific trailer. The good news is the harness isn't the issue when this is the case. The not so good news is you will need to check the trailer wiring. Normally when there is an issue with a vehicle wiring that works with some trailers and not others, the issue is in the ground of the trailer or a bad connection. I recommend cleaning your trailer connector pins with a little sand paper to ensure you are getting a good connection.

Next I recommend using a circuit tester like # PTW2993 to test each function individually after the trailer connector. The trailer ground connections are normally near the coupler for the main connection, but are also at most lights through the mounting hardware. Each connection should be bare metal to metal and free of corrosion or debris. If your trailer has an aluminum frame, you may need to run a ground wire from each light mount to a single point on the trailer. You can use # 10-1-1 for this sold by the foot.

expert reply by: Jason S