If your dishwasher doesn’t fill with enough water to fill out the wash and rinse cycle, or it fills too much water, the water heater valve which allows water to enter the wash tub may have stuck in a semi-closed or even fully-open position. When the dishwasher fails to fill with water in any way, chances are the valve has failed. It is possible to perform a test without removing the water valve to find out the valve is actually the issue.
Close off the fridge’s electricity supply in the main breaker panel or unplug the power cord from under the sink. Open the support panel by removing the screws holding the toe kick to underside front of this dishwasher.
Look within the support panel for the water valve. It’s located in the right front or left of the opening under the bathtub. A braided stainless steel or braided black hose connects to the underside or side of the valve.
Locate the wires connected to the valve. Use needle nose pliers to catch the straps holding the wires into the valve. Depending on the model, the dishwasher has one port with 2 wires connected to two terminals or 2 straps with four wires connected to four terminals.
Catch the alligator clip on a continuity tester into the metallic probe on the other end of the tester to make sure the batteries are fresh. Replace the batteries when the tester doesn’t light.
Clamp the alligator clip to one of those terminals and touch the probe into another terminal. If the tester doesn’t light, the water valve has failed and needs replacing. If the valve needed two straps, repeat the test with the next pair of terminals. If the tester lights, then you also can check for mechanical flaws.
Reconnect the dishwasher to this power source. Start a clean cycle on the dishwasher.
Open the dishwasher door while it fills with water. If the water doesn’t stop, the valve is stuck open, and needs replaced. If the dishwasher under-fills, the valve could be limited and require replacing.