Program stops during wash or rinse; dishwasher drains repeatedly and shows E03.

Safety first: Unplug the dishwasher and close the water tap. Heating components operate at mains voltage and can cause electric shock.

• Check for obvious wiring damage: Remove the left or right side panel (depending on model) to access the flow heater assembly on the circulation pump. Inspect the wiring harness and connectors for burns or loose contacts.
• Verify water temperature: Run a short hot program and, after 15–20 minutes, carefully open the door (pause program first) to check if the water is warm. If it is cold and E03 appears, the heater circuit is likely faulty.
• Basic reset: Disconnect power for 5–10 minutes, then reconnect and try another cycle. If E03 returns, further diagnosis is needed.
• Advanced checks (for skilled users): With the appliance unplugged, measure resistance of the heater and NTC sensor at the heater assembly using a multimeter. An open circuit heater or out-of-range NTC indicates replacement is required.
• When to call a technician: If you are not trained to work with electrical components, have a professional replace the flow heater or repair the control module.