Machine shows E05 and may stop during steam or milk frothing operations.

Safety first: Unplug the appliance and allow it to cool completely. Steam circuits can retain pressure and heat.

• Clean steam nozzle and milk system: Remove the milk frother or steam wand tip and soak it in warm water with a little dish soap. Use the supplied cleaning needle or a fine pin to clear any blocked holes.
• Run steam cleaning program: If your Bosch model has a milk system cleaning program, run it with the recommended Bosch cleaning agent to remove milk residues.
• Descale the machine: Limescale in the steam thermoblock can cause overheating. Run a full descaling cycle.
• Check ventilation: Ensure the built-in unit has proper airflow and that vents are not blocked by cabinetry or objects.
• If E05 remains: The steam NTC sensor or steam thermoblock may be faulty. Replacement requires opening the unit and working near high-voltage components; professional service is recommended.