Not sure what the difference may be on a 1999 vs 2002 but here are a couple things to check
Each door under the slide has an inhibitor switch that senses when the door is closed. When my slide doesn't move the first thing I try is slamming all the doors shut.
I have a slide control module that is located in my passenger side rear electrical bay. It is fastened to the door of that first compartment. Looks like this
https://rvpartsexpress.com/product/k...kibsoc1020awd/ there is a fuse that blows occasionally I think its a 5 amp.