Refrigerator shows E3; defrost cycles seem irregular, frost builds up on evaporator or freezer rear wall.

Safety first: Disconnect mains power before working inside the freezer or near wiring.

Access the evaporator area:

• Empty the freezer compartment and remove drawers and shelves.
• Unscrew and remove the rear interior panel to expose the evaporator coil and fan.

Inspect the defrost/evaporator sensor:

• Locate the small sensor clipped to the evaporator tubing or attached with a metal clip or plastic holder.
• Check for heavy ice buildup around the sensor, broken insulation, or corroded wires.
• Ensure the sensor is firmly attached to the coil; a loose sensor can misread temperature.

Defrost and test:

• If the evaporator is heavily iced, allow it to fully defrost (leave doors open, towels on floor). Do not chip ice with sharp tools.
• Once dry, inspect the sensor wiring for cracks or breaks.
• Optionally, test resistance with a multimeter; an open or shorted sensor must be replaced.

Replace if faulty:

• Install a Finlux-compatible evaporator/defrost NTC sensor in the same position on the coil.
• Secure wiring away from the fan and heater.

Reassemble and test: Refit the rear panel and shelves, restore power, and monitor for 24–48 hours. The E3 code should clear and frost buildup should reduce.

Note: If E3 remains, the main control PCB's defrost circuit may be defective and require professional replacement.