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 InformationEngine Coolant Temperature Warning Light
This light comes on briefly while
starting the vehicle.
If it does not, have the vehicle serviced by your dealer. If the system is working
normally the indicator light goes off.
Caution
The engine coolant temperature warning light indicates that the
vehicle has overheated. Driving with this ...
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 ...
Instrument Panel Illumination Control
This feature controls the brightness of the instrument panel controls and infotainment
display screen. The thumbwheel is to the left of the steering column on the instrument
panel.
(Instrument Panel Brightness):
Move the thumbwheel up or down to brighten or dim the instrument panel contr ...