Display shows E4 and the unit may defrost too often or form heavy ice on the evaporator.

Safety: Unplug the cooler. Be cautious of sharp evaporator fins.

• Access evaporator: Remove interior back panel in the affected zone to expose the evaporator coil. This may require removing shelves and trim.
• Locate sensor: The evaporator NTC is usually clipped directly to the coil or attached with an aluminum clip or tape.
• Check attachment: Ensure the sensor is firmly in contact with the coil. If it has fallen off, reattach using a new clip or aluminum tape rated for refrigeration use.
• Inspect wiring: Look for ice damage or pulled wires. If insulation is cracked or conductors are exposed, replace the sensor assembly.
• Replace sensor: Install a new evaporator NTC sensor and route the harness along the original path, avoiding pinch points when reinstalling the panel.
• Manual defrost: Before reassembly, fully defrost any heavy ice buildup using towels and ambient air (do not use sharp tools or high heat).