The window contact switch batteries are flat.
Replace the window contact switch batteries.
Vapor extraction for the cooktop does not work (KMDA 7774, KMDA 7774-1, CSDA 1040). If the window contact switch battery is flat, the window contact switch does not transmit any signal to the receiver. The window contact switch does not enable any voltage for operating the vapor extraction. Vapor extraction therefore does not work.
Replace the window contact switch batteries.
Check the breaker in the building’s wiring system.
Vapor extraction still does not work.
Please contact Miele Customer Service.