Display shows E3; ice production may stop or be inconsistent, and temperature readings may be inaccurate.

Safety first: Disconnect power and shut off the water supply to the refrigerator before working near the ice maker.

Steps:

• Locate the ice box thermistor: On Viking models with a dedicated ice compartment, the thermistor is usually clipped to the ice box wall or housing.
• Inspect sensor and wiring: Check for broken clips, frayed wires, or ice buildup around the sensor.
• Test the thermistor: Disconnect and measure resistance with a multimeter. Compare to spec for the given temperature. Replace if open, shorted, or out of range.
• Check harness to ice maker and control: Ensure connectors are fully seated at both the ice maker assembly and the main control board.

Corrective action: Replace the ice box thermistor if faulty. Restore power and water, then allow several hours for the system to stabilize and the error to clear.