S 600 Sedan (140.057) V12-6.0L (120.982) (1996)
Cabin Ventilation Duct: Description and Operation
After ventilation of the passenger compartment, air exits from the vehicle through the rear ventilation.
Louvers in the rear vent open as a result of the pressure from the air flowing through the vehicle allowing it to flow out.
If a vacuum is present in the vehicle due to a window or the sliding roof being open while driving, the louvers close automatically from the force of
gravity. This prevents exhaust gases, dust and moisture from being sucked in.