Open the Whirlpool dishwasher and remove the bottom rack.
Look for food chunks or residue on the bottom of the tub and wipe it clean with a damp cloth.
Grab the filter assembly, which looks like a circular mesh piece, and make ¼ turn counterclockwise to lift up and out. Gently pull the filter assembly and filter cup apart and wash with running water and a soft cloth. Set the filter assembly back into the dishwasher and slide the tabs into the corresponding slits in the dishwasher. Place the filter cup into the filter assembly and turn clockwise slowly until it slides into position. Continue turning clockwise until the filter locks.
Remove any hard objects or wet paper from the food grinder, which is located next to the filter assembly in some models and is sometimes called the wash module. Wipe the grinder clean with a damp cloth.
Unscrew the bottom spray arm and lift the spray arm out to access the interior of the spray arm where the wash and drain impellers are located. Look for objects blocking the rotation of the impeller fans and clean as needed. Replace the spray arm.