Diagnostics
OnStar Vehicle Diagnostics will
perform a vehicle check every
month. It will check the engine,
transmission, antilock brakes, and
major vehicle systems. It also
checks the tire pressures, if the
vehicle is equipped with the Tire
Pressure Monitoring System. If a
diagnostics check is needed
between e-mails, push 
, and an
Advisor can run a check.
See also:
Recommended Fluids and
Lubricants
Fluids and lubricants identified below by name, part
number, or specification can be obtained from your
dealer/retailer.
...
Before Leaving on a Long Trip
Make sure you are ready. Try to be well rested.
If you must start when you are not fresh — such as
after a day’s work — do not plan to make too
many miles that first part of the journey. We ...
Retrieve My Number
1. Push . System responds:
“OnStar ready.”.
2. Say “My Number.” System
responds: “Your OnStar
Hands-Free Calling number is.” ...