A specific set of Call Home messages will cause Smart Call Home to create a case with TAC. For a list of those messages, refer to the Smart Call Home monitoring details document here:
http://www.cisco.com/en/US/services/ps2827/ps2978/ps7334/SCH_Monitoring_Details.pdf. The SR column indicates those messages that will cause Smart Call Home to raise a case.
Smart Call Home will hold an eligible message for a short period of time before creating a case. If a recovery message is received within that window, Smart Call Home will not create a case.
Smart Call Home calculates this window by comparing its own current time to the time provided by the managed device. Thus, it is critical that the system time on the managed device is accurate because any difference in the system time may impact the size of the window. It is recommended that a reliable time source is used for all managed devices.