1997 GMC Sonoma Owner's Manual - Page 127

AM-FM Stereo with Compact Disc Player and Automatic Tone Control (If Equipped) and wind noise as you drive. Set the volume at the desired level. Move the control ring behind the upper knob clockwise to adjust the SCV. Then, as you drive, SCV automatically increases the volume, as necessary, to overcome noise at any particular speed. Thevolume level should always sound the same to you as you drive. If you don't want to use SCV, turn the control all the way down. Each detent on the control ring allows for more volume compensation at a fasterrate of speed. Finding a Station AM-FM: Press thisbutton to switch between AM, FM1 and FM2. The display will show your selection. Playing the Radio PWR-VOL: Press this knob to turn the system on and off. To increase volume, turn the knob clockwise. Turn it counterclockwise to decreasevolume. The knob is capable of rotating continuously. RECALL: Display the time with the ignition off by pressing this button. When the radio is playing, press this button to recall the station frequency. SCV Your system has a feature called Speed-Compensated-Volume (SCV). With SCV, your audio system adjusts automaticallyto make up for road TUNE: Press this knob lightly so it extends. Turn it to choose radio stations. Push the knob back into its stored position when you're not using it. SEEK: Press the light arrow to tune to the next higher station and the left arrow to tune to the next lower station and stay there. The sound will mute while seeking. SCAN: Press and hold SEEK for two seconds until SCAN appears on the display. SCAN allows you to listen to stations for a few seconds. The receiver will continue to scan and momentarily stop at each station until you press the button again. The sound will mute while scanning. 3-13