Compass Magnetic Variation Adjustment

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Magnetic variation adjustments are required when the compass displays a constant error in heading. Variation is the difference between magnetic north and true north due to geographical location.

Fig 1: View Of World Magnetic Variation Map

Courtesy of GENERAL MOTORS CORP.

Fig 2: Illustrating Magnetic Variation Zones

Courtesy of GENERAL MOTORS CORP.

Locate your current geographic location on the World Magnetic Variation Map.
Turn ON the ignition, with the engine OFF.
Press and hold the switch for the compass, which may be depicted as COMP, COMPASS, or on/off (w/UE1) depending on the type of mirror on the vehicle, until a zone number appears on the compass display.
Depress the switch for the compass to select the desired zone number.
Wait 5 seconds. The display will return to a compass heading. The variance procedure is now complete.
Calibrate the compass. Refer to Compass Calibration mentioned above.