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:
Additives
To provide cleaner air, all gasolines in the
United States are now required to contain additives
that will help prevent engine and fuel system
deposits from forming, allowing your emission
control ...
Replacement Bulbs
For replacement bulbs not listed here, contact your
dealer/retailer. ...
Your Responsibility
You may need to increase the volume of your
radio to hear the OnStar® advisor. If the light next
to the OnStar® buttons is red, this means that
your system is not functioning properly and should
...