See also:

Charging System Light
The charging system light comes on briefly when the ignition is turned on, but the engine is not running, as a check to show the light is working. The light turns off when the engine is started. ...

Climate Control Influence on eAssist Operation and Fuel Economy (If Equipped)
The climate control system is dependent upon other vehicle systems for heat and power input. Certain climate control settings can lead to higher fuel usage and/or fewer auto stops. The follo ...

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 ...