Lexus ES300 Owner's Manual page 191

Push the "MUTE" button to decrease the volume
momentarily.
To return to its original volume, push the same button again.
When the audio system is turned on, the mute is always off
regardless of the previous mode.
Push the "AM", "FM", "TAPE" or "DISC" button to turn on
that mode. The selected mode turns on directly.
Push these buttons if you want to switch from one mode to
another.
If the tape or disc is not set, the cassette player or compact disc
player does not turn on.
You can turn off the cassette player by ejecting the cassette
tape. If the audio system was previously off, then the entire
audio system will be turned off when you eject the cassette
tape. If another function was previously playing, it will come on
again.
AUDIO
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