Installed a used Bosch dishwasher. Ran a test regular wash cycle. It went through the full cycle and even signalled the cycle was complete. When the door was opened water was still circulating in the bottom (pump was running). Drain line from dishwasher is clear from unit to high point vent/drain.

When I tried to cycle on/off the unit returned to draining mode, but still no dishcharge to the drain.

Where should I look first, second, third, etc...