See also:

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 ...

How the System Works
When the vehicle is started, both outside mirror displays will briefly come on to indicate that the system is operating. While driving forward, the left or right side mirror SBZA display will ...

Brake Fluid
The brake master cylinder reservoir is filled with DOT 3 brake fluid. See Engine Compartment Overview for the location of the reservoir. There are only two reasons why the brake fluid level ...