Service All-Wheel Drive Light

This light should come on briefly when you turn on the ignition, as a check to show you it is working.
The service all-wheel drive light comes on to indicate that there may be a problem with the drive system and service is required. Malfunctions can be indicated by the system before any problem is apparent, which may prevent serious damage to the vehicle. This system is also designed to assist your GM dealer in correctly diagnosing a malfunction.
See also:
California Perchlorate Materials Requirements
Certain types of automotive applications, such as airbag initiators, seat belt pretensioners, and lithium batteries contained in Remote Keyless Entry transmitters, may contain perchlorate materials.
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How the System Works
When the vehicle is started, both outside mirror displays
will briefly come on to indicate that the system is
operating. While driving forward, the left or right side
mirror SBZA display will ...
Vehicle Identification Number (VIN)
This is the legal identifier for your vehicle. It
appears on a plate in the front corner of the
instrument panel, on the driver’s side. You can see
it if you look through the windshield from ou ...
