Lexus 2004 GX470 Owner's Manual page 252

Using your audio system: some basics
This section describes some of the basic features of the Lexus
audio system. Some information may not pertain to your
system.
NOTICE
To prevent the battery from being discharged, do not
leave the car audio on longer than necessary when the
engine is not running.
Your audio system adjusts to the optimum volume and tone
quality automatically. While the system is adjusting the audio
sound, the audio sound fades out and then fades in.
Your audio system works when the ignition switch is in the
"ACC" or "ON" position.
Finish
AUDIO
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