For service and parts needs, visit your dealer. You will receive genuine GM parts and GM-trained and supported service people.
Genuine GM parts have one of these marks:

Vehicle Care
California Proposition 65 WarningSIR Identification Views
The SIR Identification Views shown below illustrate the approximate location
of all SIR components available for the vehicle. This will assist
in determining the appropriate SIR Disabling and Enabling for a given service
procedure, refer to SIR Disabling and Enabling.
Front End Sensor-- ...
Quick Info
Quick Info gives access to quick information on Audio playing, OnStar Turn-by-Turn
route (if equipped), 5-day forecast, Nearby Fuel Stations, and Movie Show Times.
To access, press Quick Info on the Home Page or the INFO button on the faceplate.
Depending on the system and if the options are ...
Turn and Lane-Change Signals
Move the lever all the way up or down to signal a turn.
An arrow on the instrument cluster will flash in the direction of the turn or
lane change.
Raise or lower the lever until the arrow starts to flash to signal a lane change.
The turn signal flashes three times.
The lever returns to its ...