Lexus GS300 1998 Owner's Manual page 213

AIR CONDITIONING AND AUDIO
20G005
" 1 Fan speed at low
2 Fan speed at high If manual switching of air intake is desired –
The fan speed can be set to your desired speed by pushing the
appropriate side of fan speed control button. The higher the
fan speed is, the more air is delivered. Pushing the "OFF"
button turns off the fan.
To remove exterior windshield frost, use the high speed
setting.
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