STANDARD PROCEDURE
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 Remote Compass Module (RCM).
The electronic compass unit features a self-calibrating design, which simplifies the calibration procedure. This feature 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 the Electronic Vehicle Information Center (EVIC) displays “CAL”, perform the following calibration procedure. Also, any time a new RCM is installed, it must be calibrated using this procedure.
Calibrate the compass manually as follows:
NOTE: 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.
1. Start the engine but leave the vehicle in “PARK” .
2. Press and release the C/T button (1) so that the EVIC display is in the Compass/Temperature mode.
3. Depress and hold the C/T push button (1) for approximately ten seconds. The message “CAL” will appear in the EVIC display.
4. To complete the compass calibration, drive the vehicle in one or more complete 360 degree circles under 5 mph (8 km/h) in an area free of large metal objects such as other vehicles, large buildings, or bridges; or, near overhead or underground power lines, until the “CAL” indicator turns off. The compass will now function normally.
NOTE: If the compass display indicates an inaccurate compass heading or the display is locked up, the RCM may be inoperative or the vehicle may need to be demagnetized. Perform the Compass Demagnetizing Procedure prior to performing any system diagnosis, (Refer to 8 - ELECTRICAL/OVERHEAD CONSOLE/ELECTRONIC VEHICLE INFO CENTER - STANDARD PROCEDURE - COMPASS DEMAGNETIZING).
NOTE: If the compass display indicates dashes “– –” the RCM may be inoperative or the vehicle may need to be demagnetized. Perform the Compass Demagnetizing Procedure prior to performing any system diagnosis, (Refer to 8 - ELECTRICAL/OVERHEAD CONSOLE/ELECTRONIC VEHICLE INFO CENTER - STANDARD PROCEDURE - COMPASS DEMAGNETIZING).
NOTE: If the “CAL” message remains in the display or if the compass heading is inaccurate following the calibration procedure and there are no internal compass faults, either there is excessive magnetism near the compass, or the unit is inoperative. Repeat the calibration procedure at least one more time prior to performing any system diagnosis.
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 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 proceed as follows:
1. Be certain that the ignition switch is in the Off position, before you begin the demagnetizing procedure.
2. Place a piece of paper approximately 22 by 28 centimeters (8.5 by 11 inches), oriented on the vehicle lengthwise from front to rear, on the center line of the roof at the windshield header. The purpose of the paper is to protect the roof panel from scratches, and to define the area to be demagnetized.
3. Connect the degaussing tool to an electrical outlet, while keeping the tool at least 61 centimeters (2 feet) away from the compass unit.
4. Slowly approach the center line of the roof panel at the windshield header, with the degaussing tool connected.
5. Contact the roof panel with the plastic coated tip of the degaussing tool. Be sure that the template is in place to avoid scratching the roof panel. Using a slow, back-and-forth sweeping motion, and allowing 13 millimeters (0.50 inch) between passes, move the tool at least 11 centimeters (4 inches) to each side of the roof center line, and 28 centimeters (11 inches) back from the windshield header.
6. With the degaussing tool still energized, slowly back it away from the roof panel. When the tip of the tool is at least 61 centimeters (2 feet) from the roof panel, disconnect the tool.
7. Calibrate the compass, (Refer to 8 - ELECTRICAL/OVERHEAD CONSOLE/ELECTRONIC VEHICLE INFO CENTER - STANDARD PROCEDURE - COMPASS CALIBRATION) and adjust the compass variance, (Refer to 8 - ELECTRICAL/OVERHEAD CONSOLE/ELECTRONIC VEHICLE INFO CENTER - STANDARD PROCEDURE - COMPASS VARIATION ADJUSTMENT).
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 setting may need to be changed.
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 position.
3. Press and release the C/T button (1) so that the EVIC display is in the Compass/Temperature mode.
4. Depress and hold the C/T push button (1) for approximately five to ten seconds. The last variance zone number will appear in the EVIC display. The default variance zone is 8.
5. Press and release the STEP button (3) until the zone number for your geographic location appears in the display.
NOTE: During programming, the Zone value will wrap around from Zone 15 to Zone 1.
6. Depress and release the RESET push button (2) to exit.
7. Confirm that the correct directions are now indicated by the compass.