[f5fstop]

Didn't know that! Guess it could be due to different software or maybe just the liability.
Except for certain emergencies such as air bag deployment, Onstar is not supposed to ping your system. However, when you sign up for the email service, you give them permission t ping your system once a month. They will then attempt to ping your system at the same time each month, and if the vehicle is not on, they will keep pinging until they get the info required.