Trailer Lights Do Not Work with Two Different Trailer Wiring Harness on a 2003 Dodge Durango

Question:

Hi bought harness, hooked it up to existing trailer harness, not working. bought new trailer harness lights and wiring, hooked it up, still not working. I dont have a multi meter to test. I bought this harness because it appeared to be plug and play without any splicing. My Durango lights and turning signals work when plugged in so I have to assume its in the converter box where there is some type of break.

asked by: Brian K

Expert Reply:

One harness not working I can understand, but 2 in a row is not likely. I suspect there is something else going on. Since harness # 118334 is the correct T-connector for your 2003 Dodge Durango to determine if the issue is with the harness or something else you will need to test it.

You do not have to have a multimeter to test it. If a neighbor has one or a circuit tester such as # PTW2992 then you can use that. Also most auto parts stores loan tools so you could inquire about borrowing a test light or meter so you will not have to buy your own.

The test is very easy. First, unplug the trailer. Then have someone sit in the Durango and go through each lighting function while you test. If there is no power on the harness then there is a problem with the wiring and it will need to be replaced. If there is power then the issue is on the trailer side.

The most likely cause is a dirty or corroded trailer connector or a bad ground connection. Make sure the connector is clean and corrosion free. Then make sure that the main trailer connector ground and the grounds for all of the lights are connected to clean and corrosion free bare metal surfaces.

I have included a link to our help article showing how to test the vehicle side wiring.

expert reply by: Michael H