Freezer beeps and displays E4; defrost cycle may not run or may run too often, causing warm temperatures or heavy frost.

Safety: Unplug the freezer. Allow any ice to melt before working around the evaporator to avoid slipping and damage.

Steps:

• Access evaporator area: Remove baskets and the rear inner panel to expose the evaporator coil and defrost components.
• Identify defrost devices: Look for a round, clip-on defrost thermostat attached to the coil, and/or a small sensor (NTC) taped or clipped to the tubing.
• Check continuity of thermostat: If the coil is cold (below freezing), the defrost thermostat should show continuity (0–1 Ω). If it is open when cold, replace it.
• Test defrost sensor: If present, disconnect and measure resistance. Compare to expected NTC values. Replace if open/shorted.
• Inspect wiring: Follow the wires from the thermostat/sensor to the control board and defrost heater. Repair any burnt, brittle, or broken wires.
• Reassemble and test: After replacing faulty parts, reassemble panels, restore power, and force a defrost cycle if your model allows (refer to service sheet behind grille or rear panel). Confirm that the heater warms the evaporator and that E4 clears.