Freezer displays E10; ice buildup may be present and defrost cycles seem abnormal.

Safety first: Unplug the freezer before accessing the evaporator and defrost components.

• Access evaporator area: Remove baskets and inner rear panel to expose the evaporator coil, defrost heater, and defrost thermostat/sensor.
• Inspect sensor and thermostat: Ensure the defrost sensor and thermostat are firmly clipped to the evaporator tubing. Loose mounting can cause incorrect temperature readings.
• Test components: With a multimeter, check continuity of the defrost thermostat when cold (should be closed). Measure resistance of the defrost sensor and compare to expected NTC values. Replace any component that is open, shorted, or out of spec.
• Check heater mounting: Confirm the heater is properly positioned along the evaporator and not touching plastic parts directly.
• Defrost manually: If heavy ice is present, fully defrost the unit (unplug, doors open) before reassembly to reset conditions.
• Reassemble and test: Replace faulty parts with Hisense-compatible components, reassemble panels, restore power, and monitor for normal defrost operation and clearing of E10.

If E10 returns with new components, the main control board may be mismanaging defrost and should be checked by a technician.