The overhead console includes two front-mounted reading and courtesy lamps, optional compass mini-trip com-
puter, with or without the universal transmitter option.

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OVERHEAD CONSOLE - SERVICE INFORMATION

STANDARD PROCEDURE

COMPASS VARIATION ADJUSTMENT

Compass variance, also known as magnetic declination, is the difference in angle between magnetic north and true
geographic north. In some geographic locations, the difference between magnetic and geographic north is great
enough to cause the compass to give false readings. If this problem occurs, the compass variance must be set.

To set the compass variance:

1. Using the Variance Settings map, find your geographic location and note the zone number.

2. Turn the ignition switch to the On/Run position. If the compass/temperature data is not currently being displayed,

momentarily depress and release the C/T push button to step through the display options until you have reached
the compass/temperature display.

3. Press and hold the Reset push button down until “VAR” appears in the display. This takes about five seconds.

4. Momentarily depress and release the STEP push button to step through the zone numbers (1-15), until the zone

number for your geographic location appears in the display.

5. Momentarily depress and release the Reset push button to enter the displayed zone number into the compass

unit memory.

6. Confirm that the correct directions are now indicated by the compass.

COMPASS CALIBRATION

CAUTION: Do not place any external magnets, such as magnetic roof mount antennas, in the vicinity of the
compass. Do not use magnetic tools when servicing the overhead console.

The electronic compass unit features a self-calibrating design, which simplifies the calibration procedure. This fea-
ture automatically updates the compass calibration while the vehicle is being driven. This allows the compass unit
to compensate for small changes in the residual magnetism that the vehicle may acquire during normal use. If the
compass readings appear to be erratic or out of calibration, perform the following calibration procedure. Also, new
service replacement compass mini-trip computer modules must have their compass calibrated using this procedure.

OVERHEAD CONSOLE - SERVICE INFORMATION

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Do not attempt to calibrate the compass near large metal objects such as other vehicles, large buildings, or bridges;
or, near overhead or underground power lines.

Note: Whenever the compass is calibrated manually, the variation number must also be reset. See Compass
Variation Adjustment in the Service Procedures section of this group.

Calibrate the compass manually as follows:

1. Turn the ignition switch to the On position. If the compass/temperature data is not currently being displayed,

momentarily depress and release the C/T push button to step through the display options until you have reached
the compass/temperature display.

2. Depress and hold the RESET push button. Hold the push buttons down until “CAL” appears in the display. This

takes about ten seconds.

3. Drive the vehicle on a level surface, away from large metal objects and power lines, through one or twocomplete

circles in not less than 16 seconds. The “CAL” message will disappear from the display to indicate that the com-
pass is now calibrated.

Note: A blank compass display indicates that vehicle degaussing (demagnetizing) is necessary.

Note: If the “CAL” message remains in the display, either there is excessive magnetism near the compass,
or the unit is faulty. Repeat the calibration procedure at least one more time.

Note: If the wrong direction is still indicated in the compass display, the area selected for calibration may be
too close to a strong magnetic field. Repeat the calibration procedure in another location.

COMPASS DEMAGNETIZING

A degaussing tool (Special Tool 6029) is used to
demagnetize, or degauss, the overhead console for-
ward mounting screw and the roof panel above the
overhead console. Equivalent units must be rated as
continuous duty for 110/115 volts and 60 Hz. They
must also have a field strength of over 350 gauss at 7
millimeters (0.25 inch) beyond the tip of the probe.

To demagnetize the roof panel and the overhead con-
sole forward mounting screw, proceed as follows:

1. Be certain that the ignition switch is in the Off posi-

tion, before you begin the demagnetizing proce-
dure.

2. Connect the degaussing tool to an electrical outlet,

while keeping the tool at least 61 centimeters (2
feet) away from the compass unit.

3. Slowly approach the head of the overhead console

forward mounting screw with the degaussing tool
connected.

4. Contact the head of the screw with the plastic

coated tip of the degaussing tool for about two sec-
onds.

5. With the degaussing tool still energized, slowly

back it away from the screw. When the tip of the
tool is at least 61 centimeters (2 feet) from the
screw head, disconnect the tool.

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