Ice maker shows EC20 or service code 20 and shuts down or runs briefly without making ice.

Safety: Disconnect power before removing panels or touching wiring. Ice bin may be heavy; remove it carefully.

Steps to address EC20:

• 1. Verify bin is correctly installed: Make sure the ice storage bin is fully seated and not misaligned, which can affect the bin sensor reading.
• 2. Locate the bin thermistor: On Sub-Zero ice makers, the bin sensor is usually mounted on or near the ice bin wall or chute. Remove the bin and look for a small sensor probe or plastic housing with wires leading to the control area.
• 3. Inspect connections: Check the harness connector at the sensor and at the control board. Clean any corrosion and reseat the connectors firmly.
• 4. Test the sensor: With power off, disconnect the bin thermistor and measure resistance with a multimeter. Compare to the Sub-Zero temperature/resistance chart for the approximate bin temperature. A reading that is open (infinite) or shorted (near 0 ohms) indicates a bad sensor.
• 5. Replace the bin thermistor: If readings are out of spec, install a new OEM bin thermistor. Route the wiring away from moving parts and sharp edges, and secure with cable ties as originally installed.
• 6. Control board check: If the sensor tests good but EC20 remains, the control board may not be reading the sensor correctly. This typically requires a professional to confirm and replace the board.

Note: Do not bypass the bin sensor; doing so can cause overfilling and potential water damage.