Big tip: Bookmark this forum.........
Common problems for 99s are the Isolator bolt issue which flags codes 171/174 and the DPFE (can't remember the codes).
They will both probably rear theirs heads at one time or another if they have not already done so.
Cruise:
My cruise wasn't working and I used a Haynes manual to allow me to "ring" out the wires and trace it to the pushbutton module on the steering column but there are other possibilities too.
Search this forum for some immediate answers and visit often. Between a few regulars here we seem to be able to maintain our Windstars and most of us are way too stuborn to pay someone to service them (or maybe too thrift)