
If equipped, some audio controls can be adjusted at the steering wheel.
: For vehicles with OnStar or a
Bluetooth system, press to interact
with those systems.
See OnStar Overview or Bluetooth (Infotainment Controls) or Bluetooth (Overview).
: Press to reject an incoming
call or end a current call. Press to
mute or unmute the infotainment
system when not on a call.
or
: Press to go to the
previous or next menu option.
or
: Press to go to the next or
previous selection.
: Press to select a highlighted
menu option.

The favorite and volume switches are on the back of the steering wheel.
Steering Wheel Adjustment
Heated Steering Wheel#03-08-46-004N: Part Restriction and Ordering Process Information for OnStar Vehicle Communication Interface Modules (VCIM) (GMNA Only) - (Aug 30, 2013)
Subject:Part Restriction and Ordering Process Information for OnStar® Vehicle CommunicationInterface Modules (VCIM) (GMNA Only)Models: 2012-2014 GM Cars and TrucksAll Equipped with OnStar® RPO UE1 This bulletin has been revised to add the 2014 model year and update ESC contact information.Please ...