Rick, I do the folowing with dishwashers:

- check to see it secured beneath the countertop
- check the door and gasket
- slide the top and bottom racks in and out
- check the tub interior for cracks or chips
- align the spray wands to make sure they turn when I run the unit (wands that don't move are a problem)
- remove the kick panel after running and draining the unit to check for leaks (find one leak and it will become part of your regular routine - not all leaks will show up on the floor outside the kick panel, only the worst)