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:
Maintenance Records
After the scheduled services are performed, record the date, odometer
reading, who performed the service, and the type of services performed in the boxes provided. Retain all maintenance
receipts. ...
Selecting a Menu Option
1. Turn the Menu knob to move the
highlighted bar.
2. Press SELECT to select the
highlighted option. ...
Automatic Transmission Fluid
How to Check Automatic Transmission Fluid
It is not necessary to check the transmission fluid level. A transmission fluid
leak is the only reason for fluid loss. If a leak occurs, take the vehicle ...
