Message Systems: Diagnosis Chrysler Pacifica CS

DIAGNOSIS AND TESTING - OVERHEAD CONSOLE

The most reliable, efficient, and accurate means to diagnose the overhead console or related system requires the use of a DRB III® scan tool and the BODY DIAGNOSTIC PROCEDURES article. The DRB III® scan tool can provide vital information to the technician trying to find a problem with a overhead console component. Diagnostic logic is built into the overhead console mounted module to help the person trying to locate the problem by the most efficient means possible. Anytime a problem is suspected, a DRBIII® scan tool must be obtained and used to retrieve any stored fault codes in the module. If diagnostic fault codes are present in the module, record them on a piece of paper immediately before proceeding any further. Then, use these fault codes to identify the problem by verifying the fault code. Example, If the module records " TIRE PRESSURE N/A " fault, locate the diagnostic procedure for this code in the BODY DIAGNOSTIC PROCEDURES article and follow the flow chart until the specific problem is located and resolved. Once the problem is thought to be corrected, erase the stored fault code using the DRB III® scan tool and verify correct system operation. If the tire pressure monitoring system is functioning correctly, verify that there are no other stored codes in the module and return the vehicle to service.

If the fault code could not be verified, such as not finding anything wrong when following the diagnostic flow chart in the BODY DIAGNOSTIC PROCEDURES article, this is a good indication that a INTERMITTENT problem may be present. You must than attempt to find the intermittent problem, such as running a tire pressure monitoring system self test. Refer to TIRES/WHEELS for more information. Always, eliminate all other potential problems before attempting to replace the module.

TESTING VOLTAGE AND GROUND SUPPLY TO OVERHEAD CONSOLE

1. Remove the overhead console from the headliner «(Refer to ELECTRICAL/OVERHEAD CONSOLE - REMOVAL)»(ref-245436-S14588370902006110200000) Disconnect the overhead console electrical connector. Check the fused B(+) circuit in the overhead console electrical connector. If OK, go to step 2 . If not OK, repair the open circuit or component as required. Refer to the «SYSTEM WIRING DIAGRAMS»(ref-172301) for detailed schematics.
2. Check the IGN RUN B(+) circuit in the overhead console electrical connector. If OK, go to step 3 . If not OK, repair the open IGN RUN B(+) circuit as required.
3. Check the Ground circuit in the overhead console electrical connector. If OK, go to step 4 . If not OK, repair the open ground circuit as required.
4. If the tire pressure monitoring system is not operating properly, replace the module with a known good unit and retest the system. Refer to «TIRES/WHEELS»(ref-245427) for more information on the tire pressure monitoring system.

DIAGNOSIS AND TESTING - AMBIENT TEMPERATURE SENSOR

1. Turn the ignition switch to the Off position. Disconnect and isolate the battery negative cable. Disconnect the ambient temperature sensor wire harness connector. Refer to «REMOVAL»(ref-245436-S03439498842006110200000) .
2. Using an ohm meter, measure the resistance through the ambient temperature sensor. At room temperature (approx. 68°F), the sensor resistance should be between 9-11 kilohms (9000 - 11000 ohms). The sensor resistance should read between these two values. If OK, the sensor is OK at this time. If not OK, replace the faulty ambient temperature sensor.

DIAGNOSIS AND TESTING - COMPASS MINI-TRIP COMPUTER

A DRB III® scan tool is required for checking the PCI Data Bus circuit and the compass mini-trip computer.

1. Remove the overhead console from the headliner. Check for battery voltage at the fused B(+) circuit cavity of the CMTC module. If OK, go to step 2 . If not OK, repair the open fused B(+) circuit as required.
2. Turn the ignition switch to the Off position. Disconnect and isolate the battery negative cable. Check for continuity between the ground circuit cavity of the CMTC module and a good ground. There should be continuity. If OK, go to step 3 . If not OK, repair the open ground circuit as required.
3. Connect negative battery cable. Turn the ignition switch to the On position. Check for battery voltage at the fused ignition switch output (run/start) circuit cavity of the CMTC module. If OK, the voltage and ground supply to the module is OK at this time. If not OK, repair the open fused ignition switch output (run/start) circuit as required.

Note. If the compass functions, but accuracy is suspect, it may be necessary to perform a variation adjustment. This procedure allows the compass unit to accommodate variations in the earth's magnetic field strength, based on geographic location. Refer to STANDARD PROCEDURE - COMPASS VARIATION ADJUSTMENT .

Note. If the compass reading displays a blank, and only "CAL" appears in the display, demagnetizing may be necessary to remove excessive residual magnetic fields from the vehicle. Refer to STANDARD PROCEDURE - COMPASS DEMAGNETIZING .

DIAGNOSIS AND TESTING - UNIVERSAL TRANSMITTER

If the Universal Transmitter is inoperative, but the tire pressure monitoring system and compass are operating normally, refer to setting transmitter codes. Retrain the Transmitter with a known good transmitter and test the Transmitter operation again. If the Universal Transmitter, Tire Pressure monitoring and compass are inoperative, refer to DIAGNOSIS AND TESTING - OVERHEAD CONSOLE for diagnosis. For complete circuit diagrams, refer to INSTRUMENT CLUSTER. If the universal transmitter is inoperative, test the transmitter with special tool Radio Frequency Detector. (Scheme 20) Procedure is as follows

1. Turn the Radio Frequency Detector ON. A "chirp" will sound and the green power LED will light. If the green LED does not light, replace the battery.
2. Hold the RF detector within one inch of the TRAINED universal transmitter and press any of the transmitters buttons.
3. The red signal detection LEDs will light and the tool will beep if a radio signal is detected. Repeat this test three times.

Scheme 20