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 InformationRoadside Assistance Program
For U.S.-purchased vehicles, call 1-800-243-8872. (Text Telephone (TTY): 1-888-889-2438.)
For Canadian-purchased vehicles, call 1-800-268-6800.
Service is available 24 hours a day, 365 days a year.
Calling for Assistance
When calling Roadside Assistance, have the following information ready:
...
Loss of Control
Skidding
There are three types of skids that correspond to the vehicle's three control
systems:
Braking Skid - wheels are not rolling.
Steering or Cornering Skid - too much speed or steering in a curve causes
tires to slip and lose cornering force.
Acceleration Skid - too much thro ...
Starting the Engine
Automatic Transmission
Move the shift lever to P (Park) or N (Neutral). The engine will not start in
any other position. To restart the engine when the vehicle is already moving, use
N (Neutral) only.
Caution
Do not try to shift to P (Park) if the vehicle is moving. If you
do, you could dam ...