See also:

Immobilizer Operation (Key Access)
This vehicle has a passive theft-deterrent system. The system does not have to be manually armed or disarmed. The vehicle is automatically immobilized when the key is removed from the igniti ...

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 v ...

Brake Fluid
The brake master cylinder reservoir is filled with DOT 3 brake fluid as indicated on the reservoir cap. See Engine Compartment Overview for the location of the reservoir. There are only two ...