Kitchenaid Dishwasher

Help!My Kitcheaid D/W fills with water for the pre-rinse, then fills again for the first main wash, but never fills again after that.Machine keeps running dry. I know the pump works because it is sending water to the arms even without filling up(its pumping whatever water is dripping off the wet dishes).I have to manually put water in with my sink spray just to keep the cycles going, but I cant do this every day. Husband is a contractor and can probably do the repair himself Thanks!