Switchover Valves
WARNING: This page is about a different car, the 1999 Mercedes-Benz CLK430, 1999 Mercedes-Benz CLK320, and 1998 Mercedes-Benz CLK320. However, it is still accessible from the selected car via links, so may be relevant.
Airflow patterns are maintained by electronic control unit. Unit causes vacuum portion of various mode switchover valves to operate their respective doors to redirect airflow.