Diagnosis
The door latch is not engaging. This is usually caused by an obstruction in the latch mechanism or misalignment of the door.
How to Fix It
Inspect the latch hook on the door and the strike plate on the tub frame. Remove any food debris, broken plastic, or foreign objects with a flashlight and tweezers. Check the rubber door gasket for folds or displacement that might block closure. Clean all surfaces. Close the door firmly until you hear a distinct click.
If That Didn't Work
The door springs may be over-tensioned, pulling the door open. This requires a mechanical adjustment of the spring tension on the door hinges, which is a precise procedure outlined in the installation manual.
Heads Up
Do not force the door closed. The latch mechanism contains a door switch that must engage for the dishwasher to run. Forcing it can damage the switch or the latch assembly.