Filter Cleaning
Next, clean any debris caught in the filter at the bottom of the dishwasher. If it is a removable filter, take it out and clean it under the faucet with running water. Use a soft nylon brush and water to clean non-removable filters. If the screen is damaged, replace it. Particles making it through the screen can plug up your pump.
Gasket Cleaning
The gasket is the rubber seal that lines the door of the dishwasher. It keeps the water from escaping during operation. If too much debris gets on the gasket, it could possibly leak. Use a paper towel and some water to clean it off.
Inspection
Lastly, inspect the dishwasher for any signs of damage or ware. Start by looking over the tines of the dish rack for damage. Over time the plastic coating can be damaged and worn away. Use a soft grade of steel wool to remove any rust from exposed metal. Then use a tine repair kit ($8-10) to cover up it up.
Check the heating element for any damage and make sure it is secure in the brackets. If you suspect it is not functioning or is damaged, a replacement can be purchased for $20-30.