Step-by-Step DIY Fix Guide
- SAFETY: Leave the machine running — do not interrupt mid-cycle.
- Mix 1 tablespoon of fabric softener with 2 cups (0.5 liters) of water.
- Pour the mixture into compartment II of the detergent drawer.
- Do not add this mixture if washing outdoor clothing, sportswear, or down items.
- Allow the cycle to complete — the machine will rinse out excess foam.
- For the next wash, reduce detergent dose by 25–50%.
- Switch to an HE-certified detergent formula.
If it's still not filling correctly
- If normal household water flow looks good but the code returns, the inlet-valve or fill-sensing path becomes more likely.
- If airflow still seems weak after the basic checks, the fan path or a deeper obstruction becomes more likely.
- If the warning returns immediately after a clean restart, the sensor or wiring path becomes more likely than a one-time glitch.
What This Error Means
E:30 / -20 on your Bosch washing machine means: The machine has detected excessive foam in the drum, or additional water was introduced mid-cycle, causing an abnormal water level reading. The machine detects this condition via its sensors and stops the current cycle to prevent further damage. The error will remain until the underlying cause is resolved.
The most frequent cause is too much detergent used for the load size. Work through the causes listed below in order — the first cause is the most likely and the most straightforward to check.
Error E:30 / -20 is DIY-safe for most homeowners. The fix typically takes under 30 minutes and requires no specialist tools. Follow the steps below exactly — skipping steps is the most common reason the error returns.
The drum will remain empty or partially filled, and the wash cycle will not progress. Turn off the water tap before inspecting the inlet hose or filters.
What users usually notice before this code
Bosch washing-machine warnings like this often appear after a fill problem, a drain slowdown, a badly balanced load, or a startup sequence that did not settle cleanly.
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.
- Treating a sensor-related warning as a guaranteed board failure before checking the simpler model-family causes first.
Most Likely Cause by Symptom
The Bosch washing machine may stop, pause, or refuse to complete the cycle normally.
Likely cause: Too much detergent used for the load size
Check first: SAFETY: Leave the machine running — do not interrupt mid-cycle.
Performance may drop because airflow, filtering, or draining is restricted.
Likely cause: Wrong type of detergent — non-HE formula in an HE front-loader
Check first: Mix 1 tablespoon of fabric softener with 2 cups (0.5 liters) of water.
Excess foam or detergent residue may be visible.
Likely cause: Old or degraded detergent foaming excessively
Check first: Pour the mixture into compartment II of the detergent drawer.
Common Causes
- Too much detergent used for the load size
- Wrong type of detergent — non-HE formula in an HE front-loader
- Old or degraded detergent foaming excessively
- Water manually added during cycle
What Not to Do
- Do not add detergent manually mid-cycle
Model and Display Variation Notes
Model-family notes
- Bosch washing machine 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
Manual and model check
Check your exact model and manual before ordering any Bosch washing machine parts.
This section stays model-first because exact manual and parts matching matters more than a generic replacement suggestion here.
When Not to Keep Troubleshooting
E30-20 recurs consistently despite using correct HE detergent at recommended dose — foam sensor may need inspection
How to Prevent It Recurring
- Use HE-certified detergent at the recommended dose
- Reduce detergent for small or lightly soiled loads
Related Error Codes
Foam/Bubbles Icon
The washing machine has detected too much foam inside the drum, usually caused by too much or the wrong type of detergent.
E33
The washing machine has detected detergent foam overflowing from the detergent drawer, caused by too much detergent or an old detergent formula.
E:30 / -10
The washing machine cannot fill with water properly. Multiple causes are possible — the display may also show a faucet icon alongside this code.
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
Before calling appliance service: the safe checks worth doing first
The simple checks that can save time, money, and a messy support call before you commit to service or parts.
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.
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 Bosch 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: 2026-04-07
Based on: Based on Bosch support material and edited into consumer-safe guidance for the exact code family on this page.
Model coverage note: Bosch washing machine 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.