Display shows E4 and unit may shut down or fail to cool properly

Warning: Always disconnect power before working near the evaporator or defrost heater. Components may have sharp edges.

• Access evaporator and defrost components: Remove interior shelves and the rear liner panel to expose the evaporator coil and defrost heater assembly.
• Locate defrost sensor: It is typically clipped to the evaporator tubing or mounted near the top of the coil. Verify it is firmly attached and not damaged.
• Check for heavy ice buildup: If the coil is encased in ice, allow the unit to fully defrost (doors open, towels in place) for several hours. Do not chip ice with sharp tools.
• Test defrost sensor: Disconnect the sensor and measure resistance at known temperatures (e.g., room temperature and in ice water). Compare to Danby’s chart. Replace if readings are out of range.
• Inspect defrost heater: With the unit unplugged, test the heater element for continuity using a multimeter. An open circuit indicates a failed heater that must be replaced.
• Check wiring and connectors: Look for burned, brittle, or disconnected wires between the heater, sensor, and control board.
• Replace faulty parts: Install a Danby-compatible defrost sensor or heater as needed. Reassemble panels, restore power, and verify that E4 clears.
• If E4 persists: The main control PCB defrost circuit may be defective and require replacement.