My trailer lites quit working, no blown fuses, all the lites on the 4Runner work. The previous day everything was fine. At the same time the gas gauge went nuts!!! It shows an empty tank, and the warning lite flashes. re-start the 4R and it might show full, next time 3/4 tank, on occasion its actual. I'm lost for a reason. I checked the connections are tight. Is there a master fuse that is for just the trailer wire harness? Is the fuel sensor tied in to it? I can live w/o the fuel guage, but need the trailer lites. BTW its factory tow pkg.