Ice maker displays EC10 or service code 10 and will not start a freeze cycle.

Safety: Turn off power and shut off the water supply before working near the inlet line.

Steps to address EC10:

• 1. Confirm water supply temperature: Extremely hot water connected to the ice maker can cause temperature faults. Sub-Zero ice makers must be connected to a cold water line only. If connected to hot, correct the plumbing.
• 2. Locate the inlet thermistor: This sensor is typically strapped or clipped to the incoming water line near the water inlet valve. Remove the front grille or lower panel to access.
• 3. Inspect mounting and insulation: Ensure the thermistor is firmly attached to the water line and covered with the factory insulation sleeve. A loose sensor can misread temperature.
• 4. Test the thermistor: With power off, disconnect the thermistor and measure resistance. Compare to the Sub-Zero chart for room temperature. Replace the thermistor if the reading is open, shorted, or far out of range.
• 5. Check wiring and board: Inspect the harness for cuts or pinched sections. Verify the connector at the control board is fully seated. If all checks pass and EC10 persists, the control board may be defective and should be evaluated by a professional.

Tip: After replacing the thermistor, restore power and allow the unit to run a full cycle to confirm the error does not return.