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 InformationStarter Switch Check
Warning
When you are doing this inspection, the vehicle could move suddenly.
If the vehicle moves, you or others could be injured.
Before starting this check, be sure there is enough room around the vehicle.
Apply both the parking brake and the regular brake.Do not use the accelerator
pe ...
Home Page (Radio with Touchscreen)
Touchscreen Buttons
Touchscreen buttons show on the screen when available. When a function is unavailable,
the button may gray out. When a function is selected, the button may highlight.
Home Page Features
Press to go to the Home Page.
audio: Press to select AM, FM, SiriusXM®
(if equipp ...
If No Steam Is Coming from the Engine Compartment
If an engine overheat warning is displayed but no steam can be seen or heard,
the problem may not be too serious. Sometimes the engine can get a little too hot
when the vehicle:
Climbs a long hill on a hot day.
Stops after high-speed driving.
Idles for long periods in traffic.
If the ...