Bosch Dishwasher Error Code E04 — Flow Sensor Fault
What this means
The E04 error indicates the flow sensor is detecting an abnormal water flow rate — either too much or too little water is passing through the system. This can be caused by a faulty flow sensor, a partially blocked spray arm, or a problem with the circulation pump.
Alternate codes: E4
Step-by-step fix
3 stepsClean the spray arms
Remove the upper and lower spray arms and clear any debris from the spray holes using a toothpick or thin wire.
Food particles and mineral deposits commonly block spray arm holes, disrupting flow patterns.
Inspect the flow sensor
Locate the flow sensor near the water inlet and check for debris buildup. Clean the sensor area thoroughly.
The flow sensor is a small turbine-style device — even a tiny piece of debris can affect its readings.
Test the flow sensor
Use a multimeter to check the sensor's resistance. If it reads open or shorted, replace the flow sensor.
A properly functioning sensor should show some resistance and change as water flows past it.
When to call a professional
If cleaning the spray arms and sensor does not resolve the issue, a technician can diagnose whether the circulation pump is at fault.
Related error codes
Information compiled from manufacturer service manuals, official troubleshooting documentation, and appliance repair industry resources. This guide is for informational purposes only — always consult a qualified technician for complex repairs.
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