2003 Mercedes CL-Class Owner's Manual - Page 163

Controls in detail Automatic climate control Air recirculation mode Switch to air recirculation mode to prevent unpleasant odors from entering the vehicle from the outside. This setting cuts off the intake of outside air and recirculates the air in the passenger compartment. Warning! 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 164) for the air recirculation mode to be activated automatically. If you have turned off the air conditioning ( page 166) or the outside temperature is below 41°F (5°C), the air recirculation mode will not switch on automatically. 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. G When the outside temperature is below 41°F (5°C), only switch to air recirculation mode for short periods to prevent window fogging. Activating Press button , ( page 159). The indicator lamp on the button lights up. i If you keep button , pressed, the side windows and the sliding/pop-up roof will be closed. 163