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:
Safety Belt Pretensioners
This vehicle has safety belt pretensioners for front
outboard occupants. Although the safety belt
pretensioners cannot be seen, they are part of the
safety belt assembly. They can help tighten t ...
Passlock®
Your vehicle has the Passlock® theft-deterrent
system.
Passlock® is a passive theft-deterrent system that
enables fuel if the ignition lock cylinder is turned
with a valid key. If a correct ke ...
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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