To unclog a dishwasher, check for debris in the drain hose after disconnecting the hose, and clean the hose thoroughly. Change the drain hose if the obstruction is hard to clear or if the hose itself is broken.
Dishwashers sometimes drain slowly when the drain hose becomes clogged. Blockage typically occurs in the part of the hose connecting to the main house drain line or in the area where the hose connects to the garbage disposal.
The first step to unclog a dishwasher is to unfasten the screws on the kickplate panel found beneath the dishwasher door. The screws are located either above or below the kickplate. Next, put a pan below the drain hose, and use pliers to pinch the wire clamp. Insert the wire clamp into the drain hose, and slowly remove the hose. Shake the hose while holding both ends to get rid of stuck debris without spilling anything. Throw the debris into the pan or a trash bin.
If some debris remain stuck inside the hose, use a garden hose to run water at full force through the drain hose to remove all of the obstruction. Reattach the hose after eliminating all debris. Arrange the hose to its original position, and change the wire clamps and the lower panel. Finally, test the dishwasher to ensure that it is functioning properly.