Display shows E4 and compressor or Peltier module does not cycle correctly; unit may shut down prematurely.

Safety: Disconnect power before removing panels or touching wiring.

Steps:

• 1. Determine cooler type: On compressor-based NutriChef wine coolers, E4 often relates to an evaporator or defrost sensor. On thermoelectric models, it may indicate an internal sensor fault.
• 2. Access evaporator area: Remove interior rear panel inside the cooled compartment (usually held by screws). Be careful not to damage foam insulation.
• 3. Locate sensor: Look for a small probe clipped to the evaporator coil or attached to the evaporator plate. Ensure it is firmly attached and not hanging loose.
• 4. Inspect for ice and moisture: Heavy ice buildup can damage wiring. Allow the unit to fully defrost (door open, unplugged, towels in place) for several hours, then recheck wiring.
• 5. Test sensor: Disconnect the sensor from the control board and measure resistance. Compare to expected NTC values. Replace if open, shorted, or far out of range.
• 6. Reattach properly: Clip the new or existing sensor securely to the evaporator in the original location to ensure accurate readings.
• 7. Control board check: If a good sensor is installed and E4 persists, the main control board may be defective and require replacement.