GE ice maker displays E4 and may stop cooling or shut down the compressor.

Safety first: Unplug the unit and allow hot components to cool before touching the condenser area.

• Access condenser area: Remove the rear or bottom service panel to expose the condenser coil and fan.
• Locate condenser thermistor: It is typically clipped to the condenser tubing or mounted near the coil with two wires leading to the control board.
• Inspect sensor and wiring: Look for melted insulation, crushed wires, or a sensor that has come loose from the tubing. Reattach the sensor firmly to the coil if it has fallen off.
• Check connectors: At the control board, unplug and replug the thermistor connector. Clean any visible corrosion.
• Replace if necessary: If the sensor is physically damaged or tests out of range, install a new GE-compatible condenser thermistor.
• Test: Restore power and monitor operation. If E4 returns, the main control board may be misreading the sensor and require replacement.