Before treating water in the bottom as a fault, know what normal looks like. Most dishwashers keep a small amount of water in the sump so the seals do not dry out. A thin film around the filter area is expected. Water covering the tub floor, or standing above the filter housing, is the real complaint.
Isolate First
Switch the dishwasher off at its breaker, or unplug it if the plug is accessible, before reaching into the tub. You will be working in water near electrical components, and the machine may otherwise try to resume a cycle. Bail out what you can with a cup and a sponge into a bucket, which makes everything afterwards easier.
Checks an Owner Can Make
- The filter: twist out the cylindrical filter and lift the flat screen underneath as the manual shows. Rinse away the food debris, grease and the labels that wash off jars and glue themselves across the mesh.
- The sump area: look for glass fragments, fruit stones, bones and bag clips sitting where water should drain.
- The air gap, if there is one on the sink deck: unscrew the cover and clear it. A blocked air gap backs water straight up into the tub.
- The disposer connection: if the drain hose runs into a garbage disposer, confirm the knockout plug was removed at installation and that the disposer is not full.
- The drain hose: check for a crushed section behind the machine or under the sink.
What Needs a Technician
If the filter, air gap and disposer are clear and water still sits in the tub after a cycle, the likely causes are a blocked or failed drain pump, a stuck check valve, or a control fault that never runs the pump. Those need the lower panel off with the machine isolated, which is not a job to do with a tub full of water and the power on.
Note whether you hear the pump try to run at the end of the cycle, and whether the kitchen sink drains normally, since a shared blockage shows up in both. Bring that to a Maytag dishwasher repair booking.