Check the float to make sure there's nothing causing it to stick in the up position. Check the float switch to make sure it opens when float is up. Also check the water jets in the spray arms to make sure they're not partially clogged. You don't want water ricocheting toward the door.

You should be able to access the float switch by removing the toe panel (two to four screws). Just look under the area where the float is in the tub. To test it, remove at least one of the were connectors that go to it. With the float in the down position, you should see continuity (no resistance[with your meter set on the lowest ohms scale]). Lift the float and the switch should open. You'll see infinite resistance on your meter (no continuity). If you get anything different, replace the switch.