Display shows E3, defrost cycles may not occur properly, frost buildup on evaporator or temperature swings.

Safety first: Unplug the freezer before removing the evaporator cover or working near wiring and heaters.

• Step 1 – Access evaporator area: Remove shelves and the rear interior panel to expose the evaporator coil. If heavily iced, allow ice to melt using towels and a fan (do not use sharp tools).
• Step 2 – Locate defrost sensor: The defrost thermistor is usually clipped to the evaporator tubing or mounted near the top of the coil.
• Step 3 – Inspect and reseat: Check that the sensor is firmly attached to the tubing and that its wiring is intact. Reseat the connector at the sensor and at the control board.
• Step 4 – Test sensor (advanced): Measure resistance at known temperatures (e.g., in ice water). Compare to JennAir specifications. Replace if readings are out of range.
• Step 5 – Restore and monitor: After replacing the sensor, reassemble panels, restore power, and monitor for normal defrost operation. If E3 returns, the main control board may require replacement.