Step-by-Step DIY Fix Guide
- SAFETY: Disconnect power at the breaker and have towels ready — there may be standing water.
- Remove the bottom rack and unscrew the filter assembly. Remove both filter pieces.
- Look into the pump cover opening (round cover beneath the filter area). Check for visible debris.
- Use needle-nose pliers to remove any visible obstructions.
- Reinstall the filter. Restore power and run a drain-only or short cycle.
- If water doesn't drain and E23 persists, the drain pump motor may have failed.
If it's still not draining
- If the drain path looks clear but the code returns, the issue is more likely in the pump path or another less accessible restriction.
- If the door closes normally but the warning keeps returning, the latch or switch path becomes more likely than a simple alignment issue.
- If airflow still seems weak after the basic checks, the fan path or a deeper obstruction becomes more likely.
What This Error Means
Error code E23 on your Thermador dishwasher indicates: There is an issue with the drain pump. This happens when the drain pump is blocked, clogged, or faulty. The appliance detects this condition through its built-in sensors and halts the current cycle to prevent further damage. Depending on the model, the code may flash on the display panel, appear on a digital readout, or cause the status lights to blink in a specific sequence. The dishwasher will not resume normal operation until the underlying fault is resolved.
The most frequent cause of error E23 is foreign object (glass, label, food debris) jammed in drain pump impeller. When this happens, the dishwasher's control board detects the abnormal sensor reading or motor response and triggers the fault code as a protective measure. Other contributing factors are listed in the causes section below — working through them in order is the fastest path to a fix.
Many cases of error E23 can be resolved with DIY troubleshooting — start with the steps below before calling a technician. If the steps do not clear the code, the fault is deeper in the system and professional diagnosis will be needed. The guide specifies clearly at which point to stop DIY work.
The most visible symptom of E23 is standing water at the bottom of the tub at the end of a cycle — the dishwasher failed to pump it out. The water may appear cloudy from food particles or detergent residue. Do not run another cycle until the fault is cleared, as this could allow water to overflow onto the floor.
What users usually notice before this code
Thermador dishwasher warnings like this often show up after standing water, slow draining, heavy food residue, or a cycle that never returned to normal at the end.
Common misdiagnoses
- Assuming the display code proves one exact failed part before the safe first checks are done.
- Blaming a pump or valve first when a blocked path, filter, hose, or household plumbing issue is still possible.
- Replacing a lock or latch too early when alignment, trapped laundry, or startup conditions may still explain the warning.
Most Likely Cause by Symptom
The Thermador dishwasher may stop, pause, or refuse to complete the cycle normally.
Likely cause: Foreign object (glass, label, food debris) jammed in drain pump impeller
Check first: SAFETY: Disconnect power at the breaker and have towels ready — there may be standing water.
Water may remain inside the appliance instead of clearing normally.
Likely cause: Failed drain pump motor
Check first: Remove the bottom rack and unscrew the filter assembly. Remove both filter pieces.
The warning may return immediately because the appliance is detecting an internal fault.
Likely cause: Drain hose clog preventing pump from evacuating water
Check first: Look into the pump cover opening (round cover beneath the filter area). Check for visible debris.
Common Causes
- Foreign object (glass, label, food debris) jammed in drain pump impeller
- Failed drain pump motor
- Drain hose clog preventing pump from evacuating water
What Not to Do
- Do not run further cycles until the fault is resolved
Model and Display Variation Notes
Model-family notes
- Thermador dishwasher display wording and code formats can vary by series.
- If your model behaves differently, check the owner manual before trying any deeper maintenance step.
Display and panel differences
- Panel wording can vary by series, so confirm the exact code pattern before buying parts.
Parts, Tools and Service Options
Common parts
- Drain pump motor ($45–$110)
- Pump cover ($10–$25)
Manual and model check
Check your exact model and manual before ordering any Thermador dishwasher parts.
Service option
Thermador service visit if the warning returns after the basic checks are complete.
Suggestions in this section are organized to support the troubleshooting flow first. Any future affiliate relationships should be disclosed clearly.
When Not to Keep Troubleshooting
Visible debris has been removed but drain pump won't run — motor likely failed
How to Prevent It Recurring
- Scrape food off dishes before loading
- Clean the filter monthly to keep the drain pump clear
Related Error Codes
Helpful guides for this problem
Guide
What to check before replacing a dishwasher drain pump
The checks worth doing before you blame the drain pump and spend money on a fix that may not be the real problem.
Guide
How to tell if a dishwasher problem is drainage or leak-protection related
How to tell whether a dishwasher water-related warning is about drainage or a more cautious leak-protection stop.
Guide
Most common Bosch dishwasher error codes and what they usually mean
A clearer look at the Bosch dishwasher codes owners run into most often and what is worth checking before booking service.
When not to keep pushing DIY troubleshooting
Use the code page for one careful first pass, then stop if the same warning returns or the appliance still cannot get back to normal operation.
Extra notes
- This page is based on Thermador support material and stays conservative where model-specific guidance may vary.
- The goal is to help you identify safe first checks before you move into parts, service, or model-specific manual lookup.
Source and model notes
Last reviewed: 2026-04-09
Based on: Based on Thermador support material and edited into consumer-safe guidance for the exact code family on this page.
Model coverage note: Thermador dishwasher code meanings can vary by series, control panel, and model family, so use this page as a safe starting point rather than a replacement for the model-specific manual.
Important: FixThisError is an independent guide, not the manufacturer. Use your model-specific manual when the panel wording or behavior differs.
Always disconnect power before inspecting appliances. If unsure, contact a licensed appliance technician.