2008 Pontiac Grand Prix Owner's Manual - Page 234

XM™ Satellite Radio Antenna System The XM™ Satellite Radio antenna is located on the roof of the vehicle. Keep this antenna clear of snow and ice build up for clear radio reception. If the vehicle has a sunroof, the performance of the XM™ system may be affected if the sunroof is open. Loading items onto the roof of the vehicle can interfere with the performance of the XM™ system. Make sure the XM™ Satellite Radio antenna is not obstructed. Chime Level Adjustment The radio is used to adjust the vehicle's chime level. To change the volume level of the chime, press and hold pushbutton 6 with the ignition on and the radio power off. The volume level will change from the normal level to loud, and LOUD will appear on the radio display. To change back to the default or normal setting, press and hold pushbutton 6 again. The volume level will change from the loud level to normal, and NORMAL will appear on the radio display. Each time the chime volume is changed, three chimes will sound to indicate the new volume selected. Removing the radio and not replacing it with a factory radio or chime module will disable vehicle chimes. 3-118