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PCI Bus Communication Failure

Possible Causes:

Testing

    NOTE: Determine which modules this vehicle is equipped with before beginning.
  1. Connect the Diagnostic Junction Port Tester (No. 8339) to the DRBIII(R) and to the Diagnostic Junction Port. Using the DRBIII(R) along with the Diagnostic Junction Port Tester, select Junction Port Tool, then PCI Bus Module Scan and follow the instructions on the DRBIII(R). Was the DRBIII(R) able to scan (I/D or communicate) with any modules? If yes, refer to COMMUNICATION in DIAGNOSTIC TROUBLE CODE IDENTIFICATION  or SYMPTOM IDENTIFICATION  tables for the related symptom(s). Perform BODY VERIFICATION TEST  . If no, go to next step.
  2. Turn the ignition off. Measure the resistance of the PCI Bus circuit between the Data Link Connector and the Diagnostic Junction Port connector. Is the resistance below 5.0 ohms? If yes, go to next step. If no, repair the PCI Bus circuit for an open between the DLC and the Diagnostic Junction Port. Perform BODY VERIFICATION TEST  .
    3. NOTE: Perform this function on each pin that is equipped with a PCI Bus circuit.
  3. Connect the Diagnostic Junction Port Tester to the DRBIII(R) and to the Diagnostic Junction Port. Using the DRBIII(R), along with the Diagnostic Junction Port Tester, select Junction Port Tool then PCI Bus Control Module Scan and follow the instructions on the DRBIII(R). Did the DRBIII(R) display No Modules Responding from any of the pins that were scanned? If yes, go to next step. If no, check the PCI Bus circuit between the DLC and the Diagnostic Junction Port connector for a short to voltage or to ground, repair as necessary. Perform BODY VERIFICATION TEST  .
  4. Disconnect the Diagnostic Junction Port Tester from the DRBIII(R). Keep the tester connected to the Diagnostic Junction Port. Turn the ignition on. Measure the voltage of the PCI Bus circuit on the Diagnostic Junction Port Tester that the DRBIIl(R), displayed No Modules Responding. Is the voltage steadily above 7.0 volts? If yes, go to next step. If no, go to step.  6 .
    5. NOTE: Turn the ignition off before disconnecting any module harness connector then turn the ignition on.
    NOTE: If the problem occurred on pins 1, 2 or 3, of the Diagnostic Junction Port tester, observe the voltmeter while disconnecting each module connector one at a time.
  5. Measure the voltage of the PCI Bus circuit on the Diagnostic Junction Port tester that previously measured above 7.0 volts. Disconnect the module harness connector(s). Is the voltage steadily above 7.0 volts with the module(s) disconnected? If yes, repair the PCI Bus circuit that measured more than 7.0 volts for a short to voltage. Perform BODY VERIFICATION TEST  . If no, replace the module that when disconnected the short to voltage was eliminated. Perform BODY VERIFICATION TEST  .
  6. Disconnect the Diagnostic Junction Port Tester cable from the DRBIII(R). Keep the tester connected to the Diagnostic Junction Port ground. Turn the ignition off. Disconnect the negative battery cable. Measure the resistance between pound and the PCI Bus circuit on the Diagnostic Junction Port Tester that the DRBIII(R) displayed No Modules Responding. Is the resistance below 100.0 ohms? If yes, go to next step. If no, go to step.  8 .
    7. NOTE: If the problem occurred on pins 1, 2 or 3 of the Diagnostic Junction Port tester, observe the ohmmeter while disconnecting each module connector one at a time.
  7. Disconnect the negative batters cable. Measure the resistance between ground and the PCI Bus circuit at the Diagnostic Junction Port tester that previously measured below 100.0 ohms. Disconnect the module harness connector(s). Is the resistance below 100.0 ohms with the module(s) disconnected? If yes, repair the PCI Bus circuit that measured below 100.0 ohms for a short to ground. Perform BODY VERIFICATION TEST  . If no, replace the module that when disconnected the short to ground was eliminated. Perform BODY VERIFICATION TEST  .
    8. NOTE: Visually inspect the related wiring harness. Look for any chafed, pierced, pinched, or partially broken wires.
    NOTE: Visually inspect the related wire harness connectors. Look for broken, bent, pushed out, or corroded terminals.
  8. Turn the ignition off. Were any problems found? If yes, repair wiring harness connectors as necessary. Perform BODY VERIFICATION TEST  . If no, test is complete.
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