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:
Airbag Readiness Light
There is an airbag readiness light on the
instrument panel, which shows the airbag symbol.
The system checks the airbag’s electrical
system for malfunctions. The light tells you if there
is an ...
What Will You See After an Airbag
Inflates?
After the frontal airbags and seat-mounted side impact
airbags inflate, they quickly deflate, so quickly that
some people may not even realize an airbag inflated.
Roof-rail airbags may still be a ...
When the System Does Not Seem to
Work Properly
If the URPA system will not activate due to a temporary
condition, the message PARK ASSIST OFF will be
displayed on the DIC and a red light will be shown on
the rear URPA display when the shift ...
