Diagnosis
A drain system obstruction. Water remains in the sump because the drain pump cannot evacuate it.
How to Fix It
First, check the household drain line. Ensure the sink drain and garbage disposal (if connected) are clear. For the dishwasher, remove the lower rack and filter assembly. Clear any debris from the filter and the sump area. Manually rotate the drain impeller in the sump to check for blockage.
If That Didn't Work
The drain pump may have failed. Listen for a humming sound when the drain portion of the cycle should be running. No sound indicates a failed pump or a clog in the internal drain hose.
Heads Up
Never put large food scraps or cooking oils into the dishwasher. The filter is not a garbage disposal. Clean the filter monthly.