Dakota Quad Cab 2WD V6-3.9L VIN X (2002)
Compass: Service and Repair
Compass Calibration
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 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 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. 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.
The compass module has 2 types of auto-calibration; Slow-Cal and Fast-Cal. Slow-cal ensures that during normal vehicle operation the compass
performs auto-calibration functions to keep the compass sensors in their proper operating range. Whenever the ignition is On and the CMTC receives
PCI bus data indicating that engine speed is greater than 0 rpm, auto-calibration is performed continuously.
If the calibration information stored in the compass module memory is not within the normal range after a power-up cycle, the compass will display
CAL. The CMTC will enter into the fast-cal mode until calibration is complete.
To enter the compass into Manual Calibration mode, perform the following steps:
1. Drive the vehicle to an area away from any large metal objects or overhead power lines.
2. Ensure that the proper variance zone is selected. See "Setting Magnetic Zone Variance."
See: Setting Magnetic Zone Variance
3. The ignition switch must be in the On position and the CMTC display must not be blank.
4. Press the C/T button to view the Compass/Temperature display.
5. Press and hold the RESET button until CAL is displayed, then release the button.
6. Drive slowly less than 5 mph (8 km/h) through one or two complete 360 degree circles. Each circle should not take less than 16 seconds to
complete.
7. CAL will remain illuminated to alert the driver that the compass is in the calibration mode.
8. After calibration is complete, CAL will turn off. If the compass appears blank, unable to be calibrated, or the compass displays false indications,
the vehicle must be demagnetized. Refer to Compass Demagnetizing Procedure.
See: Compass Demagnetizing