Display shows E4 and the ice maker or ice room temperature is abnormal; ice production may stop.

Safety: Unplug the refrigerator before working on the ice maker or door wiring.

Steps:

• Locate the ice room sensor: In Sharp models with a dedicated ice compartment, the sensor is usually behind a small cover near the ice maker or in the ice storage area.
• Inspect the sensor and harness: Remove the cover and check the sensor body and wires for damage, moisture, or corrosion. Reseat any plug-in connectors.
• Test the thermistor: Disconnect the sensor and measure resistance. Compare to expected NTC values; open or shorted readings indicate a bad sensor.
• Check door harness (if ice maker is in the door): Inspect the wiring where it passes through the door hinge area for pinched or broken wires.
• Replace the sensor: Install a Sharp-compatible ice room thermistor and secure it in the original location.

If E4 remains after sensor and wiring checks, the ice maker control or main PCB may be faulty and should be evaluated by a technician.