The display shows E4, and the compressor does not run or stops shortly after starting.

Safety: Unplug the wine cooler. Some defrost heaters and their wiring can be live and hot during operation.

• Access evaporator area: Remove the internal rear panel to expose the evaporator, defrost heater, and defrost sensor.
• Inspect defrost sensor: Look for a small probe clipped to the evaporator or embedded in foam. Check for physical damage or broken wires.
• Check heater continuity: Disconnect the heater leads and measure resistance with a multimeter. A typical heater will show finite resistance (e.g., 50–300 Ω). An open circuit indicates a failed heater.
• Test defrost sensor: Measure resistance at room temperature and compare it to other NTC sensors. Open or shorted readings indicate failure.
• Replace faulty parts: Install a new "Candy defrost NTC sensor" or "Defrost heater" as required. Ensure all connections are insulated and secure.
• If heater and sensor are good: The defrost relay or control circuit on the main PCB may be defective. Replace the "Main control board (PCB)" or consult a technician.