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:
Engine Air Cleaner/Filter
When to Inspect the Engine Air Cleaner/Filter
Inspect the air cleaner/filter at the scheduled maintenance intervals and replace it at the first oil change after each 80 000 km (50,000 mi) interval. S ...
Climate Control System (With Air Conditioning)
Climate Control System (With Air Conditioning)
A. Fan Control
B. Temperature Control
C. Air Delivery Mode Control
D. Air Conditioning
E. Outside Air
F. Air Recirculation
G. Rear Window Defo ...
If a Tire Goes Flat
It is unusual for a tire to blow out while driving, especially if the tires are maintained properly. See Tires on page 10‑37. If air goes out of a tire, it is much more likely to leak out slowly ...