2005 GMC Sierra 1500 Pickup Owner's Manual - Page 290

Audio Steering Wheel Controls PROG (Program): Press this button to play a station you have programmed on the radio preset pushbuttons. The radio will only seek preset stations with a strong signal that are in the selected band. When a cassette tape is playing, press this button to play the other side of the tape. When a CD is playing in the CD changer, press this button to go to the next available CD, if multiple CDs are loaded. If your vehicle has this feature, some audio controls can be adjusted at the steering wheel. They include the following: If your vehicle has OnStar®, press this button to interact with the OnStar® system. See the OnStar® manual provided with your vehicle for more information. If your vehicle does not have OnStar®, press this button to silence the system. Press it again, or any other radio button, to turn on the sound. Q SOURCE R: Press this button to switch between FM1, FM2, AM, or XM1 or XM2 (if equipped), or a cassette tape or CD. The cassette or CD must be loaded to play. Available loaded sources are shown on the display as a tape or a CD symbol. Q SEEK R: Press the up or the down arrow to go to the next or to the previous radio station and stay there. The radio will only seek stations with a strong signal that are in the selected band. When a cassette tape or CD is playing, press the up or the down arrow to fast forward or reverse. g (OnStar/Voice Recognition): Q VOLR (Volume): Press the up or the down arrow to increase or to decrease the volume. 3-124