Dishwasher shows E9 and may trip the household circuit breaker or stop heating.

Safety first: If the appliance is tripping the RCD or breaker, do not repeatedly reset it. Unplug the dishwasher and leave it disconnected until inspected.

• Visual inspection: Access the heater assembly under the tub. Look for signs of water leaks, corrosion, or burn marks around the heater terminals and wiring.
• Dry the area: If there is moisture, dry thoroughly and identify the source of the leak (e.g., hose clamp, seal, or heater body).
• Insulation test (for professionals): A megohmmeter is normally used to test insulation resistance between heater terminals and earth. Low resistance indicates a leaking heater.
• Replace heater: If the heater is suspected, replace the flow-through heater assembly with a CDA-compatible part. Ensure all seals and clamps are correctly fitted.
• Check earth connection: Confirm that the earth wire is securely attached to the chassis and heater bracket.
• If unsure: Because this involves earth leakage and potential shock risk, it is advisable to use a qualified technician.