See also:

Ending a Call
Press to end a call. ...

Horn
Press near or on the horn symbols on the steering wheel pad to sound the horn. ...

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