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
vehicle is equipped with the Tire
Pressure Monitoring System. If a
diagnostics check is needed
between e-mails, push 
, and
an Advisor can run a check.
See also:
Antilock Brake System (ABS) Warning Light
For vehicles with the Antilock Brake System (ABS), this light comes on briefly
when the engine is started.
If it does not, have the vehicle serviced by your dealer. If the system is working
nor ...
Brake Adjustment
Every time the brakes are applied, with or without the vehicle moving, the brakes
adjust for wear. ...
Special Application Services
. Severe Commercial Use Vehicles Only: Lubricate chassis components every 5
000 km/3,000 mi.
- Have underbody flushing service performed once a year. ...