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:
What to Add
If the vehicle has DOT 3 brake fluid, as indicated on the reservoir cap, use
only new DOT 3 brake fluid from a sealed container. See Recommended Fluids and Lubricants
.
If the vehicle has DOT 4 b ...
Automatic Operation
The system automatically controls
the fan speed, air delivery, air
conditioning, and recirculation in
order to heat or cool the vehicle to
the desired temperature.
When the AUTO indicator lig ...
Tire Pressure Monitor System
The Tire Pressure Monitor System (TPMS) uses radio and sensor technology to check
tire pressure levels. The TPMS sensors monitor the air pressure in your tires and
transmit tire pressure readings ...
