A dishwasher drains through a hose, 1.2 to 1.8 m (4 to 6 feet) long, into the waste disposal or sink drain. It's normal to find a pool of water inside the dishwasher after a cycle. However, if you find excess water, dirty water or food residue on dishes, it may be a sign that the dishwasher drain hose is clogged or kinked. If the drain hose is dirty or clogged, you can remove it and flush it out.
Turn off the circuit breaker that controls the dishwasher.
Open the dishwasher door. Locate the two small screws holding the bottom valance trim piece. Remove the screws and the valance, revealing the lower pump assembly and drain-hose connection.
Remove the hose clamp. Disconnect the drain line by pulling the hose.
Find the other end of the drain line under the sink; it is connected to the drain tail piece or the waste disposal. Remove the hose clamp and disconnect the drain line. The dishwasher drain hose is now disconnected at both ends.
Pull the dishwasher drain hose into the sink base through the hole between the dishwasher and the sink base.
Take the dishwasher drain hose outside or to a sink. Run hot water through the line to clean and unclog it. When you see water running freely through the hose, then it is clean. If the hose cannot be cleaned, replace it with a new drain hose of the same size and length.
Feed the clean dishwasher drain hose back to its original configuration. Reconnect both hose clamps. Reinstall the valance, turn on the circuit breaker and test-run the dishwasher.
Before beginning, remove everything from under the sink so you have room to work.
Don't pull or pry on any part, or you might create a leak elsewhere.