battery cables

Okay i screwed up went to change battery's on my Rpod 179 which has two batteries didnt take a pic im hoping someone with the same setup can tell me what the white cable is and where to i connect it im thinking negative, the trailer does have a hook up for solar. i took it to the dealer and they weren't even sure.

White is used as neutral just like your home wiring. So that should connect to -12vdc which is grounded to the chassis. That should be true throughout your trailer unless someone has miswired it.

The confusion comes from the use of two different wire color code standards in RVs, the National Electric Code (white neutral, colored wires hot (typically black or red) and the automotive standard (black negative, red positive). The NEC does apply to RVs btw, they are not cars.

Because it's such a source of confusion and many owners WI d up miswiring, I generally recommend using a multimeter to confirm what you think you have before making connections. In this particular case, the fact that the wires are taped together as StephenH points out, makes it clear what goes where.