Compass Variance (Zone) Procedure
1. Do not set the compass zone when the vehicle is moving.
Only set it when the vehicle is in P (Park).
Press the vehicle information button until PRESS 
TO CHANGE COMPASS ZONE displays.
2. Find the vehicle's current location and variance zone number on the map.
Zones 1 through 15 are available.
3. Press the set/reset button to scroll through and select the appropriate variance zone.
4. Press the trip/fuel button until the vehicle heading, for example, N for North, is displayed in the DIC.
5. If calibration is necessary, calibrate the compass.
See “Compass Calibration Procedure” following.
See also:
Parade Dimming
This feature automatically prohibits the dimming of the instrument panel displays in daylight while the headlamps are on so that the displays are still able to be seen. ...
Using Softkeys to Control a USB Storage Device or iPod
The five softkeys below the radio display are used to control the functions listed below.
To use the softkeys:
1. Press the first or fifth softkey below the radio display to display the functions li ...
Cooling System
If the vehicle has the Duramax® Diesel engine, see the Duramax® Diesel Supplement for more information.
The cooling system allows the engine to maintain the correct working temperature.
5.3 L En ...