Diagnostic Aids: Notes

WARNING: This page is about a different car, the 2003 Oldsmobile Bravada, 2003 GMC Envoy XL, 2003 GMC Envoy, and 2003 Chevrolet TrailBlazer. However, it is still accessible from the selected car via links, so may be relevant.

The customer concern may have been due to a lack of cellular service in a given area. A failure in the National Cellular Network infrastructure at the time of the customer's failed connection that has since been repaired may also have been the cause.
If an OnStar Emergency call is able to successfully connect the vehicle to the OnStar Call Center when an OnStar Call Center button press is not, there may be a failure in the ability of the OnStar system in the vehicle to be recognized by the local cellular carrier.
If the prompt OnStar request ended is heard, without pressing the white dot button at the end of the OnStar keypress, the OnStar system at one time has made a successful cellular connection, but was unable to complete the call. If repeated calls are placed with this result, contact General Motors Technical Assistance Center.