Display shows E4 and compressor or fans may not run correctly

Safety: Disconnect power before accessing the evaporator or control board. Sharp metal edges may be present; wear cut‑resistant gloves.

• Access evaporator area: Remove interior shelves and the rear interior panel to expose the evaporator coil and defrost components.
• Locate defrost sensor: The defrost thermistor is usually clipped to the evaporator tubing or mounted near the defrost heater. Inspect for physical damage or dislodged mounting.
• Check wiring: Follow the sensor and heater wires back to the main control board. Look for burnt connectors, broken wires, or signs of overheating.
• Test defrost thermistor: With the unit unplugged, disconnect the thermistor and measure resistance. Compare to the GE spec for the approximate coil temperature (often below freezing). Replace if readings are not within range.
• Test defrost heater: Disconnect heater leads and measure resistance with a multimeter. A typical heater will show finite resistance (not open). If open, replace the defrost heater assembly.
• Control board: If both thermistor and heater test good, the defrost relay or circuit on the main control board may be faulty. Replace the board if E4 persists after component checks.