Welcome to IRV2
There were several models of the Cruise Air, some with different layouts. My (Georgie Boy Landau) water pump is under the large closet in the bedroom. If you turn the pump switch on and open a faucet you should hear it running.
The owners manual for the 98 Cruise Air is here: http://www.coachmenrv.com/OwnersManuals/13920441.pdf
Georgie Boy was bought out by Coachmen)
The specifications for the 2000 Cruise Air is here, should be similar to the 98. Georgie Boy: Cruise Air
hope this helps..