Troubleshooting Trailer Wiring that Stops Working When Coupler Touches Hitch Ball
Published 09/06/2023
Question:
My trailer lights work perfectly if the car and trailer are not connected at the hitch. When I put the coupler on the ball the lights go out. Im connecting a utility trailer to a 2016 Mercedes e350. Trailer wiring is all new, and works perfectly if not connected to the car. Thanks
asked by: Ralph R
Expert Reply:
There's a short to the frame on your trailer that is causing the trailer wiring to then totally short out when it's connected to the metal ball of your trailer. What this means is you need to go over the trailer wiring looking for any exposed metal that is touching the frame and fix as needed.
Product Page this Question was Asked From
T-One Vehicle Wiring Harness with 4-Pole Flat Trailer Connector
- Custom Fit Vehicle Wiring
- Trailer Hitch Wiring
- Vehicle End Connector
- Powered Converter
- No Tow Package
- 4 Flat
- Plug and Lead
- Plug-In
- Tekonsha
more information >
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