Lexus ES-300 2001 Manual page 264

AUDIO
20E205
Push this button on the upper side to step up the (b) Presetting a station
station band or on the lower side to step down.
Your radio automatically changes to stereo reception
when a stereo broadcast is received. "ST" appears on
the display. If the signal becomes weak, the radio
reduces the amount of channel separation to prevent the
weak signal from creating noise. If the signal becomes
extremely weak, the radio switches from stereo to mono
reception. In this case, "ST" disappears from the
display.
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