Display shows E0 and the interior temperature reading is clearly inaccurate or fluctuates wildly.

Safety first: Unplug the Grundig wine cooler from the mains before removing any panels. Do not work on live circuits.

• Power reset: Disconnect power for 5–10 minutes, then reconnect. If E0 clears temporarily but returns, continue with checks.
• Inspect cabinet sensor: Locate the cabinet temperature sensor (NTC) usually clipped to the evaporator cover or mounted on the rear interior wall. Check for physical damage, corrosion, or a sensor that has fallen out of its clip.
• Check wiring and connectors: Trace the sensor wires to the main control board. Ensure the plug is fully seated, pins are not bent, and there is no moisture or corrosion. Reseat the connector several times.
• Test the NTC: With a multimeter set to resistance, measure the sensor at room temperature. Compare the reading to a Grundig NTC chart (commonly 5k–10kΩ at 25°C). If it is open (infinite) or shorted (near 0Ω), the sensor is faulty.
• Replace sensor if faulty: Order a compatible Grundig cabinet NTC temperature sensor. Remove the old sensor from its clip or bracket, route the new sensor along the same path, and connect it to the PCB.
• Check main PCB if sensor is OK: If the sensor tests good but E0 persists, the main control board may be misreading the signal. Inspect the board for burnt components or water damage. Replacement of the PCB is usually required and may be best done by a technician.