Troubleshooting A Faulty Left Turn Signal On A 2005 Jeep Grand Cherokee

Question:

I have a 2005 Jeep Grand Cherokee with factory equipped tow harness. I have suddenly lost turn signal left side yellow wire on the trailer ONLY. There is no voltage reading coming out of the yellow wire at the plug of the vehicle. The vehicle turn signals still work. Can I add a new wiring harness or do I need to totally remove old system and rewire.

asked by: Tomm F

Expert Reply:

There are a few things you will want to check before you resort to replacing the system.

First you will want to check for loose wires on the rear of the vehicle's trailer connector in addition to corrosion in the vehicle's trailer connector itself. After this is done you will then want to test the yellow wire at the back of the vehicle's trailer connector to ensure power is passing to the connector. If there is voltage present the problem is in the trailer connector and you will need a new one if the wire is properly secure.

For a new trailer connector, you can use the T-One Vehicle Wiring Harness with 4-Pole Flat Trailer Connector part # 118381 for 4-way connectors and the Hopkins Endurance Quick-Install 7-Way Trailer Connector part # HM42190 for 7-way connections.

If there is not a charge present on the yellow wire just before the connector, you will need to start tracing the yellow left turn signal back as far as you can looking for any damaged sections. If there are no frays or breaks in the wire then you will also need to check for a blown fuse responsible for that circuit.

I have attached our wiring help article for your review.

expert reply by: Conner L