Sebring LXI Convertible V6-2.7L VIN R (2002)
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 RPM is greater than zero, 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 with enter into the fast-cal mode until calibration is complete. To enter the compass into Manual Calibration mode, perform the
following steps:
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Drive the vehicle to an area away from any large metal objects or overhead power lines.
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Ensure that the proper variance zone is selected. See "Setting Magnetic Zone Variance"?
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The ignition switch must be in the On position and the CMTC display must not be blank.
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Press the STEP button and scroll to the Compass/Temperature display.
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Press and hold the STEP and US/M buttons simultaneously until CAL begins flashing and then release the buttons.
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CAL is displayed without flashing.
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Drive slowly, less than 4 MPH (8KPH) in 3 complete 360 degree circles.
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CAL will remain illuminated to alert the driver that the compass is in the calibration mode.
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After calibration is complete? CAL will turn off.
If the compass appears unable to be calibrated or the compass displays false indications, the vehicle may need to be demagnetized.
AMBIENT TEMPERATURE SENSOR
The ambient air temperature is monitored by the PCM and displayed by the CMTC. The PCM receives a hardwired input from the ambient temperature
sensor (ATS). The ATS is located on the inside of the front bumper beam.
The ATS cannot be adjusted or repaired and, if faulty or damaged, it must be replaced.
The ATS is a variable resistor that operates on a 5-volt reference signal circuit hardwired from the PCM. The resistance in the ATS changes as the
outside temperature rises or falls. The PCM senses the change in reference voltage through the ATS resistor. Based on the resistance of the ATS, the
PCM is programmed to correspond to a specific temperature. The PCM then transmits the proper ambient temperature to the BCM. The BCM filters the
ambient temperature data and transmits this data to the CMTC.
DIAGNOSIS AND TESTING
SELF-CHECK DIAGNOSTICS
The CMTC is capable of performing a diagnostic self check on its internal functions. CMTC diagnostics may be performed using a DRBIII(R) or by
using the following procedure:
1. With the ignition switch in the OFF position,depress and hold the STEP and the US/M buttons.
2. Turn the ignition switch to the On position and release the buttons.
3. of the VFD segments will illuminate for 2-4 seconds. Check for segments that do not illuminate or illuminate all the time.
4. When the self-check is complete the CMTC will display one of the following five messages:
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F (FAIL)
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P (PASS)
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Bus (No PCI bus communication)
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Bus 1 (No PCM bus messages received)
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Bus 2 (No BCM bus messages received)
5. To exit the self-check mode, depress the STEP button or cycle the ignition switch and the CTM will return to normal operation.
If a Bus fault is displayed, refer to the symptom list. If an F is displayed, the CMTC must be replaced. The CMTC will not display an F for a VF segment
that does not illuminate.
AMBIENT TEMPERATURE SENSOR
The outside temperature function is supported by the ambient temperature sensor (ATS), a signal and ground circuit hardwired to the PCM, the BCM,
and the CMTC display.
If the CMTC display indicates 60° C (140° F) or the ATS sense circuit is shorted to ground, the temp display will be 60° C (140° F) to indicate a
SHORT circuit condition.
If the CTM display indicates -45° C (-49° F) or the ATS sense circuit is open, the temp display will be -45° C (-49° F) to indicate an OPEN circuit
condition.
If there is an OPEN or SHORT circuit condition, it must be repaired before the CMTC VFD can be tested. The ATS is supported by the PCM. ATS fault
DTC's will be recorded in the PCM.
The ATS can be diagnosed using the following Sensor Test. Test the ATS circuits using the diagnostics in the Body Diagnostic Procedures Manual. If
