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:
Outside Air Temperature Display
A new outside temperature reading will be
displayed if the vehicle has been off for more than
three hours. If the vehicle has been off for less
than three hours, the old temperature reading may
be ...
Servicing Your Airbag-Equipped Vehicle
Airbags affect how your vehicle should be
serviced. There are parts of the airbag system
in several places around your vehicle. You do not
want the system to inflate while someone is
working on yo ...
Recommended Fluids and
Lubricants
Fluids and lubricants identified below by name, part
number, or specification can be obtained from your
dealer/retailer.
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