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:
If Steam Is Coming from the Engine Compartment
WARNING
Steam from an overheated engine can burn you badly, even if you just open the hood. Stay away from the engine if you see or hear steam coming from it. Just turn it off and get everyone awa ...
DIC Warnings and Messages
Messages are displayed on the DIC to notify the
driver that the status of the vehicle has changed
and that some action may be needed to correct the
condition. Multiple messages may appear one
afte ...
Brake Adjustment
Every time the brakes are applied, with or without the
vehicle moving, the brakes adjust for wear. ...
