Built-in Siemens microwave with sensor cooking shows E10 and cancels sensor programs.

Safety warning: Internal sensor modules are near live parts. Only clean accessible cavity surfaces; do not remove covers unless qualified.

Steps to try:

• 1. Clean the cavity: Wipe the interior walls and ceiling with a mild detergent solution to remove grease and residue that can affect sensor readings. Dry thoroughly.
• 2. Ventilate: Leave the door open for 30 minutes to allow moisture to escape.
• 3. Reset power: Unplug the microwave for 5 minutes, then reconnect.
• 4. Test manual modes: If manual time/power programs work but sensor programs show E10, the humidity sensor is likely at fault.
• 5. Technician-level: Access the humidity sensor (often located behind a grill in the cavity or on the top), check its connector, and measure sensor values according to Siemens service data. Replace the humidity sensor module if out of range.

Until repaired, avoid using automatic sensor programs and use manual time/power settings instead.