2002 GMC Sonoma Owner's Manual - Page 199

AUTO VOL (Automatic Volume): Your system has a feature called automatic volume. With this feature, your audio system adjusts automatically to make up for road and wind noise as you drive. Set the volume at the desired level. Press this button to select MIN, MED or MAX. Each higher choice allows for more volume compensation at faster vehicle speeds. Then, as you drive, automatic volume increases the volume, as necessary, to overcome noise at any speed. The volume level should always sound the same to you as you drive. If you don't want to use automatic volume, select OFF. RCL (Recall): Push this knob to display the station being played or to display the clock. Pushing this knob with the ignition off will display the clock Finding a Station AM FM: Press this button to switch between AM, FM1 and FM2. The display shows your selection. TUNE: Turn this knob to select radio stations. SEEK : Press the right or left arrow to go to the next or previous station and stay there. The sound will mute while seeking. SCAN : Press and hold either SCAN arrow for two seconds until SC appears on the display and you hear a beep. The radio will go to a station, play for a few seconds, then go on to the next station. Press either SCAN arrow again to stop scanning. If you press SCAN for more than four seconds, the radio will change to preset scan mode. The sound will mute while scanning. To scan preset stations, press and hold either SCAN arrow for more than four seconds, PRESET SCAN will appear on the display. You will hear a double beep. The radio will go to a preset station stored on your pushbuttons, play for a few seconds, then go on to the next preset station. Press either SCAN arrow again to stop scanning presets. The sound will mute while scanning. t u t u 3-45