Troubleshooting Left Rear Trailer Light That Glows with Vehicle Turned Off
Updated 05/27/2024 | Published 04/02/2014 >
Question:
about 9 months after installation that seemed trouble free, I am finding that the left rear tail lights are glowing when vehicle is off. what gives?
asked by: Bruce T
Expert Reply:
It sounds like there may have been a short on your trailer that caused the converter box of Curt Wiring Harness part # C56330 to short out and now there is a low amount of voltage on your left rear tail light.
We see this problem a lot, and actually the # C56330 did its job and protected your vehicle wiring. They are designed to act like a fuse between your trailer wiring and vehicle wiring so that you do not damage your vehicle wiring.
You can further test the converter box by testing the circuits going into the box by function and then testing the output side as well.
What you will need to do is find the short on your trailer wiring and fix it as necessary and then install a new wiring harness. Look for obvious signs of shorts like cut or exposed wires.
I attached an FAQ on trailer wiring plus an FAQ on troubleshooting 4-way installs.
Product Page this Question was Asked From
Curt T-Connector 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
- Hidden
- CURT
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Joel B.
5/25/2024
I had a short while replacing a bulb with the lights on; it blew the 10 amp main power fuse. When I replaced the fuse with the car lights off, the trailer tail lights came on. It appears the switch box must have burned the relay in the on position. With a main power fuse this should have been protected. This seems like a design flaw. At this point it appears I am stuck having to buy another wiring harness!? Please advise.