Unable to Connect to OnStar Message
If there is limited cellular coverage or the cellular network has reached maximum capacity, this message may come on. Push 
to try the call again or try again after driving a few miles into another cellular area.
See also:
Driver Information Center (DIC) (With DIC Buttons)
If your vehicle has DIC buttons, the information below explains the operation of this system.
The DIC displays information about your vehicle. It also displays warning messages if a system problem is ...
Selecting the Right Engine Oil
Selecting the right engine oil depends on both the proper oil specification and viscosity grade.
See Recommended Fluids and Lubricants on page 11‑12. ...
USB Supported File and Folder Structure
The radio supports:
• Up to 700 folders.
• Up to eight folders in depth.
• Up to 65,535 files.
• Folder and file names up to 64 bytes.
• Files with an .mp3 or .wma file extension.
• ...