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:
Reducing Speed While Using
Cruise Control
If the cruise control system is
already activated:
• Move the thumbwheel toward
SET/− and hold until the desired
lower speed is reached, then
release it.
• To slow down in small am ...
Radio(s)
Radio with CD (MP3)
: Press to turn the system on
and off. Turn to
increase or decrease the volume.
BAND: Press to choose between FM, AM, or XM™,
if equipped.
: Select radio stations.
...
Highbeam On Light
This light comes on
when the high-beam
headlamps are in use. ...