See also:

Turn and Lane-Change Signals
An arrow on the instrument panel cluster will flash in the direction of the turn or lane change. Move the lever all the way up or down to signal a turn. Raise or lower the lever until the arrow ...

Horn
Press on the steering wheel pad to sound the horn. ...

Add-on Electrical Equipment
The OnStar system is integrated into the electrical architecture of the vehicle. Do not add any electrical equipment. See Add-On Electrical Equipment. Added electrical equipment may interfer ...