Microwave shows F3E0 and may stop cooking prematurely or refuse to start sensor cycles.

Safety: Disconnect power before accessing internal components.

• Locate humidity sensor: On many KitchenAid over-the-range microwaves, the humidity sensor is mounted in the upper cavity area behind a small grill or cover.
• Inspect sensor and wiring: Remove the cover and check that the sensor is firmly mounted and its connector is fully seated on the harness.
• Clean sensor area: If there is heavy grease or food residue around the sensor opening, clean it gently with a damp cloth and mild detergent, then dry completely.
• Reset power: Restore power and test a sensor cook function. If F3E0 returns, the humidity sensor is likely defective.
• Replace sensor: Order the correct KitchenAid humidity sensor for your model and replace it, transferring any mounting hardware from the old sensor.