Service Bulletins
Service Bulletins give additional technical service information needed to knowledgeably service General Motors cars and trucks.
Each bulletin contains instructions to assist in the diagnosis and service of the vehicle.
See also:
Compass Variance
Compass variance is the difference between earth’s
magnetic north and true geographic north. The
mirror is set to zone eight upon leaving the factory.
It will be necessary to adjust the compass ...
How OnStar Service Works
: This blue button connects you
to a specially
trained OnStar advisor to verify your account information
and to answer questions.
: Push this red emergency button to
get priority help
fro ...
Backglass Antenna
The AM-FM antenna is integrated with the rear window defogger, located in the
rear window. Make sure that the inside surface of the rear window is not scratched
and that the lines on the glass are ...
