OnStar Vehicle Diagnostics can perform a vehicle check every month. It will check
the engine, transmission, antilock brakes, and other major vehicle systems. It also
checks the tire pressures, if the vehicle is equipped with the Tire Pressure Monitoring
System. If an On-Demand Diagnostics check is needed, press
, and an Advisor can run a check.
Connections
OnStar Additional InformationHands-Free Phone
General Information without Touchscreen
To use the hands-free phone on vehicles
without a touchscreen radio, press ,
select Onstar Hands-Free Calling, then enter the desired number.
General Information with Touchscreen
Vehicles with a Hands-Free Phone system can use a Bluetooth-capable cell p ...
Tire Terminology and Definitions
Air Pressure: The amount of air inside the tire pressing outward on each square
inch of the tire. Air pressure is expressed in kPa (kilopascal) or psi (pounds per
square inch).
Accessory Weight: The combined weight of optional accessories. Some examples
of optional accessories are automatic t ...
Antilock Brake System (ABS)
This vehicle has ABS, an advanced electronic braking system that helps prevent
a braking skid.
When the vehicle begins to drive away, ABS checks itself.
A momentary motor or clicking noise might be heard while this test is going on,
and it might even be noticed that the brake pedal moves a lit ...