Unit powers on but will not start cooking; pressing Start does nothing and no error code is shown.

Safety first: Unplug the unit before opening the housing. Do not bypass safety switches for regular use.

Step-by-step checks:

• Basket fully inserted: Remove and firmly reinsert the basket/drawer until it clicks. Some models will not start unless the basket is perfectly seated.
• Try different functions: Attempt to start multiple presets and manual modes. If none start, suspect the Start key or safety switch.
• Check door/basket switch: Access the microswitch and verify it clicks when the basket is inserted. Test continuity with a meter if available.
• Inspect Start button: On mechanical keypads, ensure the Start button has a positive click and is not stuck. On touch panels, clean the area thoroughly.
• Board connections: Reseat the connectors from the keypad/touch panel to the main control board.

When to stop: If the switch and keypad test good but the unit still will not start, the main control board may be defective. Professional diagnosis is recommended.