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:
Rear Climate Control System (Rear Climate Control Only)
A. Fan Control
B. Temperature Control
C. Air Delivery Mode Control
For vehicles with the rear climate control system, the controls are located on the rear of the center console. The system can al ...
Cleaning Exterior Lamps/ Lenses and Emblems
Use only lukewarm or cold water, a soft cloth, and a car washing soap to clean
exterior lamps and lenses. Follow instructions under "Washing the Vehicle" later
in this section. ...
Auxiliary Roof-Mounted Lamp
If the vehicle has this feature, this button includes wiring provisions for a dealer or a qualified service center to install an auxiliary roof lamp.
This button is located on the overhead console. ...