Microwave will not start; display shows F1 shortly after pressing Start.

Safety first: Unplug the microwave or switch off the circuit breaker before removing any panels. High-voltage components inside a microwave can retain a dangerous charge even when unplugged. Do not touch the magnetron, capacitor, or high-voltage wiring.

• Power reset: Disconnect power for 5–10 minutes, then restore power and test. Sometimes the control locks up due to a transient fault.
• Check for control lock: Ensure the child lock/control lock is not enabled. Refer to the user manual for the specific key combination to unlock.
• Inspect keypad ribbon cable: If you are experienced and comfortable removing the control panel, carefully remove the top/side cover, then remove the control panel assembly. Check the flat ribbon cable from the keypad to the electronic control module for corrosion, moisture, or looseness. Reseat the connector fully.
• Look for moisture or cleaning residue: If the keypad area has been heavily cleaned, allow it to dry for several hours. Do not spray cleaner directly on the panel; spray onto a cloth instead.
• Replace faulty parts: If F1 persists, the touch control panel or user interface PCB is likely defective and should be replaced as a complete assembly. This is typically a low-voltage repair but still requires care; if unsure, contact a Miele technician.