Troubleshooting 2018 Jeep Wrangler JL Running Lights Using Diode Tow Bar Wiring Kit

Updated 10/09/2018 | Published 10/08/2018

Products Featured in This Question

Roadmaster 4-Diode Universal Wiring Kit for Towed Vehicles - 7-Way to 6-Way Coiled Adapter Cord

(3186)

$179.96

Hook Probe Circuit Tester

(60)

$12.27

Question:

When I went to test the lights with my motor home, all lights worked fine except for the running tail lights, only the side marker lights lit up not the rear lights when the tail lights on motor home where on.

asked by: Andy C

Expert Reply:

When installing a diode kit like the Roadmaster Diode 7-Wire to 6-Wire Flexo-Coil Wiring Kit # RM-15267 on your 2018 Jeep Wrangler JL, you will want to first check the wiring locations to make sure they match as it is easy to get the locations mixed up. Then make sure the diodes are connected correctly so the signal is passing through correctly. You will want to use a circuit tester like # PTW2993 to check the signal at each connection point first.

The running lights on the motor home should be on the 11 o'clock pin on the 7-way. Then the 6 way should have the running lights in the 12 o'clock position. I've attached an article to assist that includes the diagrams of each.

If all of this checks out, then check your ground connections as one function not working is often the sign of a poor ground connection that isn't bare metal to metal. If you still do not have function, then you will want to probe the wire insulation to check for a short in the wire.

I've attached some article to help further.

expert reply by: Jason S