Diagnostic Aids

WARNING: This page is about a different car, the 2003 GMC Sierra, 2003 GMC Cab & Chassis Sierra, 2003 Chevrolet Silverado, and 2003 Chevrolet Cab & Chassis Silverado. 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 or a failure in the National Cellular Network infrastructure that has since been corrected.
If the prompt OnStar Request Ended is heard without depressing 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 the General Motors Technical Assistance Center.
Inaccurate or aged Global Positioning System (GPS) position may have been due to the temporary loss of GPS signal reception by the vehicle in instance such as driving through tunnels or parking structures which restrict the navigation antenna from a clear view of the satellites in the sky.

Fig 1: Onstar Symptom Diagnosis (Steps 1 - 7)

Courtesy of GENERAL MOTORS CORP.

Fig 2: Onstar Symptom Diagnosis (Steps 8 - 17)

Courtesy of GENERAL MOTORS CORP.