Unplug the unit from the wall or shut down the power at the circuit breaker if it's hardwired.
Remove water from the inside the unit using a bucket or cups. Clear out as much water as possible.
Remove the screws from the kick-plate at the bottom of the machine.
Locate the drain hose connected to the washer pump underneath the machine and put a small drain pan underneath.
Pinch the wire clamp attached to the hose and the pump with a pair of pliers and pull the hose off. Drain the water into the pan. Remove the other end of the hose by pinching the clamp with a pair of pliers. Bend the hose in different places to remove the clog. Place the hose in your sink and pour water through it to remove the blockage.
Open up the machine and pull out the wire basket. Unscrew the filter basket at the bottom of the machine and pull it out. Remove any debris.
Grab the small piece of plastic at the front of the pump area, pull forward and lift out. Inspect the inside of the pump and remove any debris. Apply a pump cleaning powder, available from your dishwasher manufacturer.
Reassemble the dishwasher by reversing the steps above.