What E04 means on your Bosch washer
Error code E04 indicates that the AquaStop leak protection system has detected water in the base pan of your Bosch washing machine. Similar to E15 on Bosch dishwashers, a float switch in the bottom tray rises when water accumulates, triggering the error and activating the drain pump to remove water from the tub as a safety measure.
Symptoms
- The washer stops mid-cycle and displays E04
- The drain pump may run continuously
- Water visible under or around the washing machine
- A damp or musty smell from the base of the unit
Common causes
- Worn door boot gasket — the large rubber seal around the door opening develops tears or cracks, especially at the fold points
- Loose hose clamp — internal hose connections to the tub, pump, or dispenser can loosen from vibration
- Tub-to-pump seal failure — the seal where the drain connects to the outer tub degrades over time
- Detergent overdose — excessive suds can push water past seals that would otherwise hold
Troubleshooting steps you can try
- Check the door boot — open the door and inspect the rubber seal for tears, holes, or debris stuck in the fold. Foreign objects like coins or underwire can puncture the boot.
- Reduce detergent — if you’ve been using regular (non-HE) detergent, switch to HE detergent and reduce the amount. Excess suds are a common leak trigger.
- Tilt and drain — carefully tilt the washer forward to drain water from the base pan, then reset by unplugging for 60 seconds.
- Run a test cycle — after reset, run a short cycle with an empty drum and watch for leaks at the door and base.
When to call a technician
E04 always indicates a real leak. A technician will pull the unit out, remove panels, and run the washer while inspecting all seal points and hose connections. The door boot is the most common replacement, followed by internal hose clamps. Ignoring E04 risks water damage to your floor and the machine’s electrical components. Codes may vary by model generation and series.
Need help? Schedule Bosch Washer repair with a certified technician, or contact our team for a free diagnosis consultation.
