Multicooker shows E11 and does not respond correctly to button presses or knob rotation.

Safety first: Disconnect power before working on the control panel. Avoid using excessive liquid cleaners near electronics.

Steps to resolve:

• Clean the control surface: Wipe the panel with a slightly damp cloth and mild detergent. Remove any sticky residue that may cause keys to stick.
• Check for physical sticking: Press each button individually to feel for sticking or lack of travel. Gently work stuck buttons to free them.
• Inspect the rotary knob (if equipped): Pull off the knob and clean around the shaft. Ensure it turns smoothly without grinding.
• Internal inspection (advanced): Remove the front panel to access the keypad PCB. Look for corrosion from liquid spills or cracked solder joints on the encoder.
• Replace faulty components: If the encoder or keypad membrane is physically damaged, replace the user interface PCB or keypad assembly with the correct Siemens part.

When to call a technician: If cleaning and basic checks do not restore normal input, professional replacement of the interface board is recommended.