The multi-band antenna is located on the roof of the vehicle. This type of antenna is used with the AM/FM radio, as well as OnStar® and the XM™ Satellite Radio Service System, if the vehicle has these features. Keep this antenna clear of snow and ice build up for clear radio reception. If the vehicle has a sunroof, the performance of the radio system may be affected if the sunroof is open. Loading items onto the roof of the vehicle can interfere with the performance of the radio system and, if the vehicle has this feature, OnStar®. Make sure the multi-band antenna is not obstructed.