George
Don't have a 98 but am working on getting a 97 up and running. Did a bit of searching and couldn't find much (other than parts are scarce). It looks like the two terminals on the tower operate a solenoid to pull the bin down. The controller is most likely a simple switch completing the circuit when you push the button. If you've got a multimeter I'd check continuity on the 98 and test the operation of the button which would be an easy replace if its bad. If the 98 shows a complete circuit I'd try hitting it with AC from a transformer say about 12VAC. If it operates or at least makes sounds like it wants to I'd open it up and try cleaning/lub. No sound/no operate again you'd need to open it up and look first for a loose connection inside.
Good luck with this rather uncommon accessory.
