2001 Chevrolet Impala Owner's Manual - Page 201

AM-FM Stereo with Cassette Tape and Compact Disc Player with Radio Data System (RDS) and Automatic Tone Control (Option) DISP: Press this button to display the clock with the ignition off. Press this button to display an RDS station frequency or program type when the radio is on. AUTO VOL: Your system has a feature called Speed-Compensated Volume (SCV). With SCV, your audio system adjusts automatically to make up for road and wind noise as you drive. Set the volume at the desired level. Press AUTO VOL to adjust the SCV. AVOL will appear on the display. Each time you press AUTO VOL, another volume setting (LOW, MEDIUM or HIGH) will appear on the display. NONE will appear on the display if the radio cannot find out the vehicle speed. Then, as you drive, SCV automatically increases the volume, as necessary, to overcome noise at any particular speed. The volume level should always sound the same to you as you drive. If you don't want to use SCV, select OFF. Each volume setting allows for more volume compensation at faster vehicle speeds. Playing the Radio PWR: Press this button to turn the system on and off. VOL: Turn this knob clockwise to increase volume. Turn it counterclockwise to decrease volume. 3-31