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:
Tachometer
The tachometer displays the engine speed in revolutions per minute (rpm).
Notice: If the engine is operated with the tachometer in the shaded warning area, the vehicle could be damaged, and the damag ...
Ashtray(s)
Notice: If papers, pins, or other flammable items
are put in the ashtray, hot cigarettes or other
smoking materials could ignite them and possibly
damage the vehicle. Never put flammable items
...
Different Size Tires and Wheels
If wheels or tires are installed that
are a different size than the original
equipment wheels and tires, vehicle
performance, including its braking,
ride and handling characteristics,
stabil ...
