Troubleshooting Trailer Wiring Harness Causing Left Tail Light to Not Work on 2004 Jeep Liberty

Question:

I purchased a wiring harness for a 2004 Jeep Liberty a year a two ago that Im having problems with now. Its causing my rear left taillight not to operate. Can you help? Thanks.

asked by: Al G

Expert Reply:

I found your order and you have the # 118524 Tekonsha wiring harness.

It's likely a short somewhere in the wire or corrosion on the connector itself. Inspect the 4-way and make sure it's clean and free of any corrosion. If you test at the 4-way using a circuit test like # PTW2993 does everything check out or is the problem here? If this problem is here then follow the wiring of the harness back to where it plugs in behind the tail lights. Also, inspect those connectors.

You didn't specify but it sounds like you're saying the issue is on the Jeep. If it's actually on the trailer then inspect the trailer's connector as well. Then you'll need to follow its wiring back to the light looking for any damage.

Also, make sure all of the ground connections are made to good, clean, bare metal surfaces.

If you still can't find the problem let me know and we'll continue to troubleshoot.

expert reply by: Charles S