1999 Lexus GS 300 Owners Manual - Page 234

AIR CONDITIONING AND AUDIO Each time you push the air intake control button, the mode changes in order from the RECIRCULATED AIR mode to AUTOMATIC mode to OUTSIDE AIR mode, then back to the RECIRCULATED AIR mode. Each indicator light shows which mode is now selected. 1 2 RECIRCULATED mode - If quick circulation of cooled air is desired, select this mode. AUTOMATIC mode - When driving where the outside air is dirty (i.e., when the vehicle running just in front of your vehicle accelerates rapidly), the system changes automatically from the OUTSIDE AIR mode to the RECIRCULATED mode. OUTSIDE AIR mode - The system will take fresh outside air into the vehicle. 3 For normal use, it is best to keep the air intake control button set to OUTSIDE AIR mode. If recirculated air is used during heating, the windows will fog up more easily. To change the sensitivity of the sensor switching between the RECIRCULATED and OUTSIDE AIR in the AUTOMATIC mode, push the air intake control button until the "AUTO" indicator light flashes. The display changes as illustrated below. The sensitivity of the sensor can be adjusted only while the vehicle has stopped. 214