2003 Mercedes CLK-Class Owner's Manual - Page 160

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! Activating Press button , ( page 155). The indicator lamp on the button lights up. If you have turned off the air conditioning system ( page 163) or the outside temperature is below 41°F (5°C), the air recirculation mode will not switch on automatically. Deactivating Press button , ( page 155). The indicator lamp on the button goes out. i If you keep button , pressed, the side windows and the sliding/pop-up roof* will be closed. 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, for example in a tunnel Please note that the charcoal filter must be activated ( page 161) for the air recirculation mode to be activated automatically. G When the outside temperature is below 41°F (5°C), only switch to air recirculation mode for short periods to prevent window fogging. i If you keep button , pressed, the side windows and the sliding/pop-up roof will be returned to their previous position. 160