Compass Magnetic Variation Adjustment

WARNING: This page is about a different car, the 2002 GMC Sierra, 2002 GMC Cab & Chassis Sierra, 2002 Chevrolet Silverado, and 2002 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.

Magnetic variation adjustments are required when the compass displays a constant error in heading.

Variation is the difference a between magnetic north and true north due to geographical location.

Fig 1: World Magnetic Variation Map

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 or 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.