Freezer shows E5 and may not defrost; ice accumulates on evaporator and fan noise may increase.

Safety: Unplug the freezer before accessing the evaporator or heater wiring. The defrost heater operates at mains voltage.

How to diagnose and fix:

• Access evaporator and heater: Remove food and shelves as needed. Take off the rear interior panel to expose the evaporator coil. The defrost heater is typically a metal or glass-encased element mounted at the bottom or woven through the coil.
• Visual inspection: Look for broken heater tubes, burn marks, or disconnected wires. Check the defrost thermostat/thermal fuse (often clipped to the evaporator tubing) for signs of overheating.
• Test heater resistance: Disconnect heater leads. Measure resistance across the heater terminals. A typical heater will read between 20–200 Ω. An open circuit (OL) indicates a failed heater that must be replaced.
• Check defrost thermostat / thermal fuse: With the evaporator cold (use an ice pack if needed), test continuity across the thermostat or thermal fuse. It should read closed (near 0 Ω) when cold. If open, replace the thermostat/fuse assembly with a Sharp-specified part.
• Inspect wiring and connectors: Trace heater wiring back to the main PCB or relay. Repair any burnt connectors or damaged wires.
• Control board / relay: If heater and thermostat test good, the defrost relay on the main PCB may not be energizing. With the unit reassembled and powered (this step is live-voltage and should be done only by qualified persons), verify whether the board outputs voltage to the heater during a forced defrost. If not, replace the main control PCB.

Final step: After replacing components, fully defrost any remaining ice, reassemble panels, restore power, and monitor for proper defrosting over the next 24–48 hours.