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:
Driving in Water
Heavy rain can mean flash flooding, and flood
waters demand extreme caution.
Find out how deep the water is before you drive
through it. If it is deep enough to cover your wheel
hubs, axles, or ...
Turning the System On or Off
VOL/ (Volume/Power): Press to
turn the system on and off.
Automatic Switch-Off
If the infotainment system has been
turned on after the ignition is turned
off, the system will turn off
autom ...
Active Fuel Management™
Your vehicle’s V8 engine may have Active Fuel
Management™. This system allows the engine to
operate on either all or half of its cylinders,
depending on your driving conditions.
When less po ...