I just bought a 2003 Eurovan camper! Whoohoo! Overall it is in great shape but the camper electrical system has something fishy going on. Any help figuring it out would be greatly appreciated.

Here are the details:
When NOT plugged in, camper's system monitor panel, fridge, heat, fluorescent light, and 110v outlets do NOT work. 12-v water pump works, however. When plugged in, heat, light, 110 outlets and fridge work, but the system monitor panel still does not work.

The deep-cell coach battery is new, and should be charged.

Do you think this is a fuse problem? If so, any suggestions?