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:
Ride Control System Messages
SERVICE REAR AXLE
This message displays when there is a problem with the All-Wheel Drive (AWD)
System. See your dealer for service.
SERVICE STABILITRAK
This message displays if there is a pr ...
Hydraulic Power Steering
Your vehicle has hydraulic power steering. It may require maintenance. See Power
Steering Fluid Power Steering Fluid .
If power steering assist is lost because the engine stops or the power s ...
Seat Adjustment
WARNING
You can lose control of the vehicle if you try to adjust a driver seat while
the vehicle is moving.
The sudden movement could startle and confuse you, or make you push a pedal
when you do ...