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

Safety first: Unplug the microwave from the mains before removing any panels. High-voltage components can retain charge even when unplugged; do not touch the high-voltage section (capacitor, transformer, magnetron).

• Step 1 – Power reset: Disconnect power for 5–10 minutes, then reconnect and test. Sometimes the control board locks up and a reset clears the F1 code.
• Step 2 – Check keypad response: Try pressing multiple keys. If some keys work and others do not, the membrane keypad is likely faulty.
• Step 3 – Inspect ribbon cable: Remove the control panel (usually a few screws behind the top grille). Carefully disconnect and reseat the flat ribbon cable from the keypad to the control PCB. Ensure it is fully inserted and not corroded or damaged.
• Step 4 – Visual inspection of UI PCB: Look for burn marks, cracked solder joints, or corrosion on the user interface board.
• Step 5 – Replacement: If the keypad film is separate, replace the membrane keypad. If it is integrated, replace the complete control panel / user interface assembly designed for your specific Bauknecht model.
• When to call a technician: If reseating the cable and power reset do not clear the error, or if you are not comfortable removing the control panel, contact an authorized Bauknecht service technician.