Error E05 displayed; defrost heater does not energize, heavy ice buildup on evaporator, fan noise from ice contact.

Safety first: Unplug the refrigerator before testing or replacing the defrost heater. The heater operates at mains voltage and can cause shock.

Step 1 – Manual defrost:

• Allow the unit to defrost fully to remove ice from the evaporator and heater area.

Step 2 – Access and inspect heater:

• Remove the rear interior panel to expose the evaporator and heater (usually a metal or glass-encased element at the bottom or woven through the coil).
• Inspect for visible breaks, burn marks, or disconnected wires.

Step 3 – Electrical testing:

• Disconnect heater leads and measure resistance with a multimeter; an open circuit indicates a failed heater.
• Check any inline thermal fuse for continuity.

Step 4 – Replace faulty components:

• Install a Fhiaba-compatible defrost heater and/or thermal fuse, ensuring proper mounting and clearance from plastic parts.
• Reconnect wiring securely and reassemble panels.
• Restore power and verify that the unit enters a defrost cycle per the service manual (technician may force a defrost test).

Note: If the heater and fuse are good but E05 persists, the main control board defrost relay or triac may be defective and should be replaced by a professional.