Display shows E03 and the air fryer shuts down shortly after starting; fan may not run.

Safety first: Unplug the appliance. Do not insert tools into the fan area while the unit is connected to power.

External checks:

• 1. Ventilation: Ensure rear and bottom vents are not blocked by walls, cloth, or other appliances. Clean dust and grease from vents with a soft brush or vacuum.
• 2. Basket fit: Confirm the frying basket and pan are fully inserted and seated. Some Bosch models will not run the fan if the basket is misaligned.

Internal checks (advanced):

• 3. Access fan assembly: Remove the rear or top cover to reach the convection fan motor and impeller above or near the heater.
• 4. Inspect impeller: Look for built-up grease, food particles, or warped plastic obstructing rotation. Gently spin the fan by hand; it should rotate freely without scraping. Clean with a degreaser and soft brush.
• 5. Test fan motor: Disconnect the motor plug. Measure resistance across the motor leads; an open circuit indicates a failed motor. If accessible, briefly power the motor with the correct mains voltage using an isolation transformer and proper safety precautions to confirm operation.
• 6. Capacitor (if present): Some motors use a small run capacitor. Inspect for bulging or leakage. Replace with the same capacitance and voltage rating if defective.

Warning: Do not operate the air fryer with the covers removed. If the fan does not run, the unit can overheat rapidly and damage internal components.