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:
Ignition Positions
The ignition switch has four different positions.
To shift out of P (Park), the ignition must be in ON/RUN or ACC/ ACCESSORY and
the regular brake pedal must be applied.
A (STOPPING THE ENGINE/ ...
When the System Does Not
Seem to Work Properly
The following messages may be
displayed on the DIC:
PARKING ASSIST OFF: This
message occurs if the driver
disables the system or if vehicle is
driven above 8 km/h (5 mph) in
R (Reverse).
S ...
Brakes
This vehicle has disc brakes. Disc brake pads have built-in wear indicators that
make a high-pitched warning sound when the brake pads are worn and new pads are
needed. The sound can come and go o ...