Turn Signals and Brake Lights Not Working On 2004 Nissan Titan Factory Tow Package Wiring

Expert Reply:

If you are testing that actual trailer connector on your 2004 Nissan Titan with a circuit tester, such as # PTW2993, then the likely culprit causing the brake and turn signals not to work is a bad or missing fuse or relay. Consult the trucks owner's manual and/or power distribution box lid to determine the locations of the fuses/relays related to the tow package wiring.

Fuses are easy to check but relays are a little harder. Basically, to test a relay you need a known good relay that you can insert in place of the potential bad one. Then you would test the trailer connector again and see if that works. The relays that you need are included in kit # C57000. The large brown relay is for the 12-volt circuit on a 7-Way and the two smaller blue relays are for the signal and brake lights.