E2 error on display and lower zone temperature is not controlled correctly

Safety first: Unplug the wine cooler before servicing.

Steps:

• Verify lower zone reading: Place a thermometer on a middle rack in the lower zone and compare to the display. If E2 is shown or the reading is erratic, suspect the lower sensor.
• Locate lower sensor: Look for a small plastic cover or vent on the rear or side wall of the lower compartment. Remove it to expose the sensor probe.
• Inspect sensor: Ensure the probe is not corroded, broken, or pulled out of its holder. Check that the wires are intact and not pinched by shelves or bottles.
• Check at PCB: Access the rear service panel and locate the main PCB. Find the connector for the lower sensor (often labeled "NTC2"). Reseat the connector and inspect for corrosion.
• Test sensor (if possible): Disconnect the sensor and measure resistance with a multimeter. Compare to the upper sensor at similar temperature; large deviation or open/short indicates failure.

Fix: Replace the lower compartment NTC temperature sensor if testing or visual inspection indicates damage. Ensure the new sensor is positioned in the airflow, not touching the evaporator directly, and that the wire pass-through is sealed.