GE ice maker shows F4 and the unit may not cool properly or may shut down intermittently.

Safety first: Unplug the unit before removing any interior or exterior panels.

• Locate ambient sensor: The ambient thermistor is often mounted near the air intake or behind a small grille on the front or side of the cabinet.
• Inspect sensor and wiring: Check for physical damage, discoloration, or loose mounting. Ensure the sensor is not dangling or touching hot components.
• Check connector: Follow the wires to the control board and reseat the connector.
• Replace sensor if needed: If the sensor is cracked or tests out of range, install a new GE ambient thermistor.
• Test operation: Restore power and verify that F4 clears and the unit cycles normally.