Diagnostic Procedure

WARNING: This page is about a different car, the 2004 Dodge Dakota. However, it is still accessible from the selected car via links, so may be relevant.

NO RESPONSE FROM PCM (PCM SCI ONLY) - NGC - DIAGNOSTIC PROCEDURE

TEST	ACTION
1	Perform the symptom Checking PCM Power and Ground Circuits in the Driveability category. NOTE: With the DRBIII(R) in the generic scan tool mode, attempt to communicate with the PCM. NOTE: If the DRBIII(R) can communicate with the PCM in the generic scan tool mode, it may not be necessary to perform this step. Did the vehicle pass this test? Yes --> Go To 2 No --> Repair as necessary. Perform POWERTRAIN VERIFICATION TEST VER - 1 .
2	Turn the ignition off. Disconnect the DRBIII(R) from the DLC. Disconnect the PCM harness connectors. Turn the ignition on. Measure the voltage of the PCM SCI Transmit circuit at the Data Link harness connector (cav 7). Is the voltage above 1.0 volt? Yes --> Repair the PCM SCI Transmit circuit for a short to voltage. Perform POWERTRAIN VERIFICATION TEST VER - 1 . No --> Go To 3
3	Turn the ignition off. Disconnect the DRBIII(R) from the DLC. Disconnect the PCM harness connectors. Turn the ignition on. Measure the voltage of the PCM SCI Receive circuit at the Data Link harness connector (cav 12). Is the voltage above 1.0 volt? Yes --> Repair the PCM SCI Receive circuit for a short to voltage. Perform POWERTRAIN VERIFICATION TEST VER - 1 . No --> Go To 4
4	Turn the ignition off. Disconnect the DRBIII(R) from the DLC. Disconnect the PCM harness connectors. Measure the resistance between the PCM SCI Transmit circuit and the PCM SCI Receive circuit at the Data Link harness connector (cavs 7 and 12). Is the resistance below 5.0 ohms? Yes --> Repair the short between the PCM SCI Transmit and the PCM SCI Receive circuits. Perform POWERTRAIN VERIFICATION TEST VER - 1 . No --> Go To 5
5	Turn the ignition off. Disconnect the PCM harness connectors. Disconnect the DRBIII(R) from the DLC. Measure the resistance between ground and the PCM SCI Transmit circuit at the Data Link harness connector (cav 7). Is the resistance below 5.0 ohms? Yes --> Repair the PCM SCI Transmit circuit for a short to ground. Perform POWERTRAIN VERIFICATION TEST VER - 1 . No --> Go To 6
6	Turn the ignition off. Disconnect the PCM harness connector. Disconnect the DRBIII(R) from the DLC. Measure the resistance between ground and the PCM SCI Receive circuit in the Data Link harness connector (cav 12). Is the resistance below 5.0 ohms? Yes --> Repair the PCM SCI Receive circuit for a short to ground. Perform POWERTRAIN VERIFICATION TEST VER - 1 . No --> Go To 7
7	Turn the ignition off. Disconnect the PCM harness connector. Disconnect the DRBIII(R) from the DLC. CAUTION: DO NOT PROBE THE PCM HARNESS CONNECTORS. PROBING THE PCM HARNESS CONNECTORS WILL DAMAGE THE PCM TERMINALS RESULTING IN POOR TERMINAL TO PIN CONNECTION. INSTALL MILLER SPECIAL TOOL #8815 TO PERFORM DIAGNOSIS. Measure the resistance of the PCM SCI Receive circuit from the Data Link harness connector (cav 12) to the appropriate terminal of special tool #8815. Is the resistance below 5.0 ohms? Yes --> Go To 8 No --> Repair the PCM SCI Receive circuit for an open. Perform POWERTRAIN VERIFICATION TEST VER - 1 .
8	Turn the ignition off. Disconnect the PCM harness connector. Disconnect the DRBIII(R) from the DLC. CAUTION: DO NOT PROBE THE PCM HARNESS CONNECTORS. PROBING THE PCM HARNESS CONNECTORS WILL DAMAGE THE PCM TERMINALS RESULTING IN POOR TERMINAL TO PIN CONNECTION. INSTALL MILLER SPECIAL TOOL #8815 TO PERFORM DIAGNOSIS. Measure the resistance of the PCM SCI Transmit circuit from the Data Link harness connector (cav 7) to the appropriate terminal of special tool #8815. Is the resistance below 5.0 ohms? Yes --> Go To 9 No --> Repair the PCM SCI Transmit circuit for an open. Perform POWERTRAIN VERIFICATION TEST VER - 1 .
9	If there are no possible causes remaining, view repair. Repair Replace and program the Powertrain Control Module in accordance with the Service Information. Perform POWERTRAIN VERIFICATION TEST VER - 1 .