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:
Dual Tone Multi-Frequency (DTMF) Tones
The in—vehicle Bluetooth system can send numbers during a call. This is used
when calling a menu—driven phone system.
1. Turn or press the MENU/ SELECT knob and select Enter Number.
2. Enter the ...
Tow/Haul Mode
The vehicle has a Tow/Haul Mode. The Tow/Haul Mode adjusts the transmission shift
pattern to reduce shift cycling, providing increased performance, vehicle control,
and transmission cooling when ...
Engine Oil Change
When the CHANGE ENGINE OIL
SOON message displays, have the
engine oil and filter changed within
the next 1 000 km/600 mi. If driven
under the best conditions, the
engine oil life system migh ...