I had a similar issue with my 2002 Suncruiser in which the HWH jacks, radio, power mirrors, defrost fans, and power driver's window did not work, however the slides did work. Turns out that it was a blown fuse and all of those things are on the same circuit. There is a fuse box under the flip open drivers dash, just lift it up and start checking. They are not labeled, however I did find a diagram of the fuses in the Workhorse chassis book that comes with the RV. The fuse was the 15 amp " ACC - radio".
There is also another fuse box under the hood, drivers side, the fuses are all labled on the inside of the lid.
I'll take a closer look at my RV when I can, there is most likely a fuse for the pump motor, it may be under the front of the RV, down near the pump. i'm not much of an expert on this stuff, just a suggestion of where to start, I'm sure that someone else will be able to tell you exactly where to look.
2002 Itasca Suncruiser