2004 Mercedes CL-Class Owner's Manual - Page 181

Controls in detail Automatic climate control Warning! G i The air recirculation mode is activated automatically: at high outside temperatures if the concentration of carbon monoxide and nitrogen oxide in the outside air increases beyond a predetermined level, for example in a tunnel. Please note that the charcoal filter must be activated ( page 181) for the air recirculation mode to be activated automatically. If you have turned off the air conditioning ( page 183) or the outside temperature is below 41°F (5°C), the air recirculation mode will not switch on automatically. Deactivating Press button , ( page 175). The indicator lamp on the button goes out. i Never operate the side windows and the sliding/pop-up roof if there is the possibility of anyone being harmed by the closing procedure. In the event that the procedure causes potential danger, the closing of the side windows can be immediately halted by releasing the , button or by pressing the respective window switch. The closing of the sliding/pop-up roof can be immediately halted by releasing the , button or by moving the sliding/pop-up roof switch in the overhead control panel in any direction. If you keep button , pressed, the side windows and the sliding/pop-up roof will return to their previous position. The air recirculation mode is deactivated automatically: after five minutes if the outside temperature is below approximately 41°F (5°C) after five minutes if the air conditioning is turned off after 30 minutes if the outside temperature is above approximately 41°F (5°C) At outside temperatures above 79°F (26°C) the system will not automatically switch back to outside air. A quantity of outside air is added after approximately 30 minutes. 180