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.
Step  | Action  | Yes  | No  | ||||||
|---|---|---|---|---|---|---|---|---|---|
Schematic Reference: OnStar Schematics Connector End View Reference: Cellular Communication Connector End Views  | |||||||||
1  | Did you perform the Diagnostic System Check - Vehicle?  | Go to Step 2  | Go to Diagnostic System Check - Vehicle in Vehicle DTC Information  | ||||||
2  | Attempt to honk the horn, operate the lights, and lock or unlock the doors on the vehicle. Does the applicable system operate properly?  | Go to Step 3  | 
 
 
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3  | 
 Important: It is necessary to inform the OnStar® Call Center advisor that this call is for vehicle diagnostic purposes. 
 Was the attempt successful?  | Go to Diagnostic Aids  | Use the scan tool to access the STID and ESN and contact the General Motors Technical Assistance Center  | ||||||