SL 500 (129.068) V8-5.0L (113.961) (2000)
Air Register: Description and Operation
Rear Ventilation
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.