Compass Magnetic Variation Adjustment

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

Locate your geographic location. See Fig 1 .
Turn ignition switch to RUN position, with engine off. Press MODE button in order to advance to COMP/TEMP mode.
With DIC in COMP/TEMP mode, simultaneously depress and hold MODE and US/MET buttons until VAR CAL is displayed, in approximately 5 seconds. Release both buttons.
Press US/MET button in order to advance to proper zone number.
Press MODE button in order to enter and set zone number.

Fig 1: Identifying Variation Zones

Courtesy of GENERAL MOTORS CORP.