Lexus 2003 LS Owner's Manual page 197

The automatic air conditioning automatically maintains
the set temperature.
This air conditioning features automatic fan speed and air
flow control which automatically selects the most suitable
fan speed and air flow to control the temperature. The
ignition switch must be in the "ON" position.
21L145
AIR CONDITIONING
NOTICE
To prevent the battery from being discharged, do not
leave the air conditioning on longer than necessary
when the engine is not running.
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