See also:

Customer Assistance for Text Telephone (TTY) Users (U.S. and Canada)
To assist customers who are deaf, hard of hearing, or speech-impaired and who use Text Telephones (TTYs), Cadillac has TTY equipment available at its Customer Assistance Center. Any TTY user can c ...

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 v ...

OnStar® Destination Download (US and Canada)
OnStar Destination Download (if equipped) is a service available for OnStar subscribers that makes operating your navigation system much simpler. It allows subscribers to request and receive navig ...