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:
Place a Call Using a Stored Number
1. Push . System responds:
“OnStar ready.” 2. Say “Call <name tag>.” System responds: “OK, calling <name tag>.” ...
When the System Does Not Seem to Work Properly
The following messages may be displayed on the DIC:
SERVICE PARK ASSIST: If this message occurs, take the vehicle to your dealer to repair the system.
PARK ASST BLOCKED SEE OWNERS MANUAL: This messa ...
Traction Control System (TCS)/StabiliTrak® Light
The StabiliTrak system or the Traction Control System (TCS) indicator/warning
light comes on briefly when the engine is started. If the light does not come on,
have the vehicle serviced by your ...