Ice maker stops mid-cycle and displays E04, ice plate or evaporator heavily frosted, ice harvest does not complete.

Safety: Disconnect power before removing covers or handling sensors.

• Locate sensors: On Zanussi ice makers, the evaporator thermistor is clipped to the evaporator plate or tubing, and the ice thickness sensor is usually near the water distribution trough or ice plate.
• Inspect for ice buildup: If sensors are encased in ice, allow the unit to defrost fully by unplugging it for several hours with towels to catch melt water. Do not chip ice with sharp tools.
• Check wiring: Follow the sensor harness back to the control board. Ensure connectors are fully seated and wires are not pinched or broken.
• Test thermistor: Disconnect the thermistor and measure resistance at room temperature. Compare to Zanussi specifications (commonly 5–10 kΩ at 25°C). Replace if readings are far out of range or open/shorted.
• Inspect ice thickness sensor: Clean any mineral deposits from the sensor surface with warm water and a soft cloth. If the sensor is cracked or corroded, replace it.
• Reset and test: Reassemble, restore power, and run a full ice cycle. If E04 returns with new sensors, the control board may be faulty and require replacement.