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:
Turning the System On or Off
VOL/ (Volume/Power):
Press to turn the system on and off ...
Engine Overheating
The vehicle has an indicator to warn of engine overheating.
There is an engine coolant temperature warning light on the vehicle's
instrument panel.
See Engine Coolant Temperature Gauge.
If t ...
Tire Rotation
If the vehicle has non-directional
tires, they should be rotated
every 12 000 km/7,500 mi.
See Maintenance Schedule.
Tires are rotated to achieve a
uniform wear for all tires.
The first rotat ...