Troubleshooting Trailer Lights Working After Trailer Tongue is Moved Up and Down

Published 09/01/2017

Question:

For me to get the turn signals, 4 ways, and brake lights to work on my utility trailer I had to lift up and down the tongue of the trailer on the ball of my hitch, but I do not have just trailer lights.

asked by: Tony

Expert Reply:

If you are having to wiggle wires around before they start to work on your trailer then you definitely have a short or a bad ground somewhere on your tow vehicle or trailer. It can also mean that you have corrosion somewhere on your wiring as well. Start off by checking the connectors and make sure that they don't have any corrosion or debris built up.

You can determine which one it is by using a Circuit Tester # PTW2979 to test each of the functions on the connector for your tow vehicle. Since you said that you have more than just trailer lights it sounds like you have a 7-Way connector. In this case you will want to make sure that when you test the pin for your brake controller (pin in the 5 O'clock position) that you set your brake controller to max power and use the manual override to send a signal to the connector.

To test the connector on your trailer you will simply need to use an alternate 12V Power source like the battery off of your tow vehicle. Test each pin on your trailer and see if the functions work properly.

By performing these tests you should be able to determine which part of your towing setup is the problem. You will then want to inspect the wiring and the all of the grounds to make sure they are solid and there are no wires that are bent, corroded, exposed, or damaged at all. Replace any wiring as necessary.

If you do all this and you still experience problems let me know and I can help you troubleshoot further.

expert reply by: Jon G