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 communicate with GMC by dialing:
1-800-462-8583. TTY users in Canada can dial 1-800-263-3830.
See also:
When the System Does Not Seem to Work Properly
The following messages may be displayed on the DIC:
SERVICE PARK ASSIST: If this message occurs, take the vehicle to your dealer to repair the system.
PARK ASST BLOCKED SEE OWNERS MANUAL: This messa ...
USB Support
The USB connector is located on the instrument panel or in the center console, and uses the USB 2.0 standard. ...
Compass Zone Setting
This display allows for setting the compass zone. See Compass on page 5‑6 for more information. ...





