E9 displayed; freezer may be excessively cold or not cold enough, with erratic temperature swings.

Safety: Disconnect power before handling sensors or control boards.

Steps:

• Verify sensor placement: Ensure the cabinet temperature sensor is properly seated in its sensor well or clipped to the correct location inside the liner. A sensor touching the evaporator or door liner can give false readings.
• Check for non-OEM parts: If the sensor was recently replaced, confirm it is the correct Avanti part number. Mismatched thermistors can cause E9.
• Inspect wiring: Look for splices, tape joints, or damaged insulation. Poor connections can cause intermittent readings.
• Test sensor resistance: Measure resistance at a known temperature and compare to Avanti's spec chart. Replace the sensor if out of tolerance.
• Control board replacement: If a correct, tested sensor still triggers E9, replace the main control board.