Bosch Dishwasher Error E23 — Meaning, Causes, and Fixes
Overview: The E23 error on Bosch dishwashers is typically a drain-related fault indicating the dishwasher cannot empty water properly. It commonly appears when the drain pump is obstructed, the drain hose is clogged or kinked, the garbage disposal connection is blocked, or the pump itself has failed electrically or mechanically. Left unresolved, E23 can lead to standing water in the tub, poor wash and rinse performance, unpleasant odors, longer cycles as the machine retries draining, and in some cases water damage or electrical stress if the fault is persistent.
Why it occurs: E23 arises when the control electronics detect an abnormal condition while attempting to pump water out. This can be caused by physical blockages that prevent the pump impeller from turning, foreign objects jamming the pump, a clogged filter or sump preventing flow, a plugged drain hose or disposal connection, or an electrical failure either in the pump motor or its wiring. Moisture or corrosion in the pump area and a faulty control board or sensor can also trigger the code.
User impact: Users usually notice standing water after a cycle, partial or poor cleaning results, persistent foul smells from old food and water, repeated error codes that interrupt cycles, and longer-than-normal washing or draining times. If ignored, the issue can escalate to water overflow, increased risk of leaks, and potential damage to internal components, which increases repair cost.
Common Causes
- Clogged or dirty filter and sump area
- Foreign objects lodged in the drain pump or impeller (glass, food debris, broken crockery, labels)
- Blocked or kinked drain hose
- Garbage disposal knockout plug not removed or disposal blockage
- Faulty or seized drain pump motor
- Stuck check valve or clogged air gap
- Wiring connections loose, corroded or damaged between pump and control board
- Faulty control board or pump relay
- Float switch or water sensor issues causing false drain fault signals
Troubleshooting Steps
- Power down and isolate the dishwasher for safety. Turn off the mains and shut the water supply before accessing internals.
- Remove the bottom rack and access the filter assembly. Clean the filter, microfilter and sump of food debris and gunk. Inspect the filter for cracks or wear.
- Visually inspect the sump and pump area for foreign objects. Remove any debris that could jam the impeller.
- Manually check the drain pump impeller for smooth rotation. If it is stuck, clear obstructions or consider pump replacement if the impeller is broken or seized.
- Inspect the drain hose for kinks and blockages. Disconnect the hose and flush it with