Running Light Circuit Not Working On Trailer Wiring Harness Installed on a 2009 Kia Sorento

Question:

I have this unit installed on a 2009 Kia Sorrento. All lights on the trailer work fine except for the running/tail lights. I tested voltage and there does not seem to be any voltage at the brown tail pin on the trailer connector. Any ideas?

asked by: Justin B

Expert Reply:

If your 2009 Kia Sorento does not have the factory tow package then the Curt trailer wiring harness # C56151 will not be correct for the vehicle and will not work properly. On vehicles that do have the factory tow package, there are usually fuses and/or relays present in the power distribution box to power the wiring harness. You can check your owners manual to determine the locations of all fuses/relays related to the tow package wiring to see if they are present and if any need to be replaced. That might be all you need to do.

Or, if you do not have the factory tow package and want the correct harness, use # C59496.

If you have the correct harness and the fuses/relays are all working and in place then it could be a problem with the converter. Use a circuit tester like # PTW2979 to test the wires going into the converter. If the signals are not correct then that indicates a problem with the vehicle wiring. If the signals are correct going in, and still not correct on the 4-Way end, then the converter is bad and will need to be replaced. I linked a video showing how to test a converter.

expert reply by: Michael H