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:
Battery Run-Down Protection
This feature helps prevent the battery from being
drained, if the interior courtesy lamps, reading/map
lamps, visor vanity lamps or trunk lamp are accidentally
left on. If any of these lamps are ...
Customer Assistance for TextTelephone (TTY) Users
To assist customers who are deaf, hard of
hearing, or speech-impaired and who use Text
Telephones (TTYs), Buick has TTY equipment
available at its Customer Assistance Center. Any
TTY user can comm ...
Vehicle Data Recording and
Privacy
Your GM vehicle has a number of sophisticated
computers that record information about the vehicle’s
performance and how it is driven. For example, your
vehicle uses computer modules to monitor ...
