Display shows E3 and the refrigerator struggles to maintain temperature, often accompanied by heavy frost on the evaporator.

Safety first: Disconnect the IceKing refrigerator from mains power before accessing the freezer evaporator area.

Steps to troubleshoot:

• 1. Defrost the unit: If the evaporator is heavily iced, power off the appliance and allow it to defrost fully (this may take several hours). Place towels to catch meltwater.
• 2. Access the evaporator: Remove freezer drawers/shelves and the rear inner panel to expose the evaporator coil. The defrost/evaporator NTC is usually clipped to the coil or attached with a metal clip.
• 3. Inspect the sensor: Ensure the sensor is firmly attached to the evaporator tubing and not hanging loose. Check for cracked casing or corroded wires.
• 4. Test resistance: With the unit unplugged, disconnect the sensor and measure resistance with a multimeter. Compare to the expected NTC value at the current temperature. Replace if open, shorted, or far out of specification.
• 5. Check wiring: Follow the harness from the sensor to the main PCB (usually at the rear, behind the lower panel). Look for pinched, cut, or corroded wires and repair as needed.
• 6. Reassemble and test: After replacing the sensor or repairing wiring, reattach the evaporator cover, restore power, and monitor for the E3 code. If the error persists, the main PCB may be faulty and should be replaced by a professional.

Warning: Do not use sharp tools to remove ice from the evaporator; you can puncture the refrigerant tubing and render the appliance non-repairable.