See also:

Engine Coolant Heater
The engine coolant heater, if available, can help in cold weather conditions at or below −18°C (0°F) for easier starting and better fuel economy during engine warm-up. Plug in the coolant ...

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), GMC has TTY equipment available at its Customer Assistance Center. Any TTY user can communicat ...

Cleaning the Display
Notice: Using abrasive cleaners when cleaning glass surfaces could scratch the glass. Use only a soft cloth and do not spray cleaner directly on the system as it could affect the mechanical parts. ...