Toyota FJ CRUISER Owner's Manual page 298

Turning the Automatic Sound Levelizer (ASL) on/off
Type A
When "ASL" is selected, turning
changes the "ASL" level in the order of "LOW", "MID" and "HIGH".
Turning
ASL automatically adjusts the volume and tone quality according to the
vehicle speed.
Type B
Turning
counterclockwise turns off the ASL.
ASL automatically adjusts the volume and tone quality according to the
noise level as you drive your vehicle.
FJCRUISER_OM_General_OM35B53W
or to the left turns "ASL" off.
clockwise turns on the ASL, and turning
3-2. Using the audio system
or to the right
3
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