See also:

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

Tachometer
The tachometer displays the engine speed in revolutions per minute (rpm). For a description of how Grade Braking affects vehicle speed while the Tow/Haul Mode is activated, see Tow/Haul Mode on page 9 ...

Using the “Delete All Name Tags” Command
This command deletes all stored name tags in the Hands-Free Calling Directory and the OnStar Turn-by-Turn Destinations Directory, if equipped. To delete all name tags: 1. Press and hold for two sec ...