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 InformationPark Brake and P (Park) Mechanism Check
Warning
When you are doing this check, the vehicle could begin to move.
You or others could be injured and property could be damaged.
Make sure there is room in front of the vehicle in case it begins to roll. Be
ready to apply the regular brake at once should the vehicle begin to move.
Park on ...
Daytime Running Lamps (DRL)
DRL can make it easier for others to see the front of your vehicle during the
day. Fully functional DRL are required on all vehicles first sold in Canada.
The DRL system makes the headlamps come on when the following conditions are
met:
The ignition is on.
The exterior lamp control is in ...
Service Publications Ordering Information
Service Manuals
Service Manuals have the diagnosis and repair information on the engines, transmission,
axle, suspension, brakes, electrical, steering, body, etc.
Service Bulletins
Service Bulletins give additional technical service information needed to knowledgeably
service General Motors c ...