Buttons beep but the air fryer will not start cooking; timer and temperature can be set but heater and fan never turn on.

Safety first: Unplug the unit before internal inspection.

Steps to get the unit to start:

• 1. Confirm basket closure: Remove and firmly reinsert the basket until it clicks. Some Hamilton Beach models require a positive latch for the start command to be accepted.
• 2. Check for error icons: Look for any door or basket icons flashing on the display that might indicate an interlock issue.
• 3. Test the interlock switch: With the unit unplugged, locate the basket/door microswitch and press it manually. You should hear a click. If not, the switch may be faulty.
• 4. Inspect wiring: Ensure the switch wires are securely connected to the control board.
• 5. Control board relay check (advanced): When you press start (with covers in place), listen for the heater and fan relays clicking. If there is no click and the interlock is good, the control board may be defective.
• 6. Replace faulty parts: Replace the basket/door microswitch if it does not actuate properly. Replace the main control board if it fails to energize the heater and fan despite correct inputs.

Note: Some models require a specific sequence (set temp, set time, then press start). Verify operation with the user manual.