Trailer Lights Only Work with Camper Plugged In To Shore Power

Updated 07/27/2012 | Published 07/25/2012

Question:

Ok here is what is going on, 1st thing I have a 12 volt deep cycle battery on my camper 4 years old. 2nd thing power inverter 30 amp I believe. Now here is what is happening, with the camper just plugged into the Truck I get no lights brake turn signal or other wise, now same setup except I also plug the camper into the household circuit and everything works just fine, brake lights running lights and turn lights, I only tried to disconnect the positive side of the battery and still had the same result as just into the truck no lights, should I disconnect the battery completely? If so and everything works I would assume the battery is bad, but why would work the way it is? is the battery the problem? Truck 2010 Nissan Titan with factory trailer package installed Brake Controller is a P-3 Tekonsha Brand new using the wiring harness that came with the controller, a TE-3050 Harness that is made for a Nissan 2004-2010.

asked by: Chuck

Expert Reply:

It sounds like the trailer lights are tied into the interior lights and the trailer mounted battery and inverter. What I recommend is to have the trailer exterior lights bypass the rest of the wiring so that the trailer connector is isolated from the other lights.

It seems that if everything is connected together through the battery or the inverter, including the trailer connector. Replacing the battery could solve the issue but I would still have the trailer connector separate from the other wiring.

expert reply by: Michael H