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 InformationTire Designations
Tire Size
The following is an example of a typical passenger vehicle tire size.
(1) Passenger (P-Metric) Tire: The United States version of a metric tire sizing
system. The letter P as the first character in the tire size means a passenger vehicle
tire engineered to standards set by the U. ...
Brake Fluid
The brake/clutch master cylinder
reservoir is filled with DOT 4 brake fluid as indicated on the reservoir cap. See
Engine Compartment Overview on page 10-7 for the location of the reservoir.
There are only two reasons why the brake fluid level in the reservoir might go
down:
The brake fl ...
Accessories and Modifications
Adding non-dealer accessories or making modifications to the vehicle can affect
vehicle performance and safety, including such things as airbags, braking, stability,
ride and handling, emissions systems, aerodynamics, durability, and electronic systems
like antilock brakes, traction control, a ...