2003 Chevrolet TrailBlazer Owner's Manual - Page 135

OnStar System Limitations Complete limitations can be found on the Subscriber Services Agreement. OnStar Service is: D available in the 48 contiguous United States, Alaska, Hawaii and Canada; D available when the vehicle is within the operating range of a cellular provider; D subject to limitations caused by atmospheric conditions, such as severe weather or topographical conditions, such as mountainous terrain; D subject to cellular carrier equipment limitations. Global positioning capabilities used to deliver OnStar service will not be available if satellite signals are obstructed. OnStar will not function if the vehicle's battery is discharged or disconnected. It may also be inoperative if the vehicle is in an accident and the OnStar or vehicle electrical system components are damaged. Safety and security services are provided by existing governmental emergency service providers. OnStar will use reasonable efforts to contact the appropriate emergency service provider and request assistance but cannot promise that they will respond to the call in a timely manner or at all. Sunroof (Option) Your vehicle may be equipped with a power sliding sunroof. To open or close your sunroof, the ignition or Retained Accessory Power (RAP) must be active. See "Retained Accessory Power" in the Index. Press and release the back of the button in the overhead console to open the sunroof. You can press the front of the button to close the sunroof. Once the sunroof is closed, press the forward side of the button to open the sunroof to the vent position. The sunroof is also equipped with a sunshade which you can pull forward to block sun rays. 2-66