Updated 10/26/2026 · AZ Tech Appliance Repair, Westmont, IL
What to check first
- The filter. Most modern dishwashers have a filter at the bottom of the tub. Twist it out, rinse it under the tap and scrub off grease.
- The garbage disposal. If the dishwasher drains through the disposal, run the disposal first. After a new disposal is installed, the knockout plug must be removed.
- The drain hose. Make sure it is not kinked behind the dishwasher or under the sink.
- The air gap on the sink, if you have one: clean it out.
Common causes we find
- A drain pump blocked by glass, a pit or a label.
- A failed drain pump.
- A stuck check valve.
- A control or sensor fault, often shown as an error code (for example E24 or E25 on Bosch).
Before you call
Write down any error code on the display and the model number from the edge of the door. Remove standing water with a cup and a towel before we arrive if you can.
Questions
Is it safe to use the dishwasher if it drains slowly?
Run it only once the filter and drain are clear. Standing water can overflow or leak.
Why does my Bosch dishwasher show E24?
Usually a clogged filter or a kinked drain hose. E25 points to something blocking the drain pump.