Diagnostic Test

1. With the scan tool, read DTCs in all Electronic Control Units (ECUs) and record on the repair order.
2. For future reference, with the scan tool, run and save a vehicle Scan Report and all related recorded data.
3. With the scan tool, erase all DTCs.
4. Turn the ignition off for 75 seconds.
5. Turn the ignition on, run the engine to operating temperature
6. Using the When Monitored and Set Conditions above and recorded data, operate the vehicle in the conditions that set the DTC.
7. With the scan tool, read DTCs.

Did the DTC return?

Yes 

• Go To  2

No 

• Perform the INTERMITTENT CONDITION diagnostic procedure. Refer to INTERMITTENT DTC .

1. Check the Batteries and charging system for proper system voltage and operation. Refer to BATTERY, 3.0L, DIAGNOSIS AND TESTING and CHARGING SYSTEM, 3.0L, DIAGNOSIS AND TESTING .

   Are the Batteries and charging system operating correctly and producing the proper system voltage?

   Yes 

   • Go To  3

   No 

   • Diagnose and repair the Batteries and charging system before continuing.
   • Perform the POWERTRAIN VERIFICATION TEST. Refer to 3.0L, POWERTRAIN VERIFICATION TEST .

1. Turn the ignition off.
2. Remove the SCR Relay 2 from the PDC.
3. Turn the ignition on.
4. Using a 12-volt test light connected to ground, probe the 12-Volt supply at terminal 85 the SCR Relay 2 connector in the PDC.

   Is the test light illuminated and as bright as a direct connection to the Battery?

   Yes 

   • Go To  4

   No 

   • Check all of the fuses in the PDC. If a fuse is open, replace the fuse and retest. If no problems are found with the fuses, check the Battery supply to the PDC and the operation of the SCR Relay 2. If no problems are found, replace the PDC in accordance with the Service Information.
   • Perform the POWERTRAIN VERIFICATION TEST. Refer to 3.0L, POWERTRAIN VERIFICATION TEST .

1. Reinstall the SCR Relay 2 in the PDC.
2. Turn the ignition on.
3. Using a 12-volt test light connected to ground, back probe the SCR Relay 2 (K402) Output circuit at the PDC connector.
   NOTE:

   The relay should make an audible click when closing. Another way to verify that the relay closed is to back probe and check for voltage on the relay output circuit.

   Did the relay close when connecting the SCR Relay 2 (K402) Output circuit to ground through the test light?

   Yes 

   • Go To  5

   No 

   • Turn the ignition off. Disconnect the PDC connector and remove the SCR Relay 2. Isolate and check the continuity between terminal 86 of the relay connector and the output terminal at the PDC connector. If the resistance is below 3.0 Ohms, replace the SCR Relay 2. If the resistance is above 3.0 Ohms, replace the Power Distribution Center (PDC) in accordance with the Service Information.
   • Perform the POWERTRAIN VERIFICATION TEST. Refer to 3.0L, POWERTRAIN VERIFICATION TEST .

1. The ignition must be off when checking a circuit for continuity to ground.
2. Isolate the circuit by disconnecting the PCM and every component harness connector containing the circuit being tested. Note:  Use the wiring diagram as a guide to follow the path of the circuit.
3. Connect the negative lead of the DVOM to a known good ground.
4. With the positive lead of the DVOM, probe the circuit being tested at the component harness connector and check for continuity between the circuit and ground.

Is there continuity between ground and the circuit being tested?

Yes 

• Repair the circuit for a short to ground. Use the wiring diagram as a guide to trace the circuit and look for any in-line connectors to help isolate the location of the short.
• Perform the POWERTRAIN VERIFICATION TEST. Refer to 3.0L, POWERTRAIN VERIFICATION TEST .

No 

• Go To  6

1. The ignition must be off when checking the continuity of a circuit.
2. Isolate the circuit by disconnecting the PCM and the component harness connector containing the circuit being tested. Note:  Use the wiring diagram as a guide to follow the path of the circuit.
3. Before measuring the resistance of any circuit, first measure the resistance between the two leads of the DVOM. Note:  The meter leads can add resistance to the measurement value.
4. Connect one lead of the DVOM to the circuit being tested at the component harness connector.
5. Connect the other lead of the DVOM to the circuit being tested at the PCM harness connector.

Is the resistance below 3.0 Ohms?

Yes 

• Go To  7

No 

• Repair the circuit for an open or high resistance.
• Perform the POWERTRAIN VERIFICATION TEST. Refer to 3.0L, POWERTRAIN VERIFICATION TEST .

1. Turn the engine off.
2. Reconnect the PDC harness connector.
3. Reconnect the PCM harness connector.
4. Disconnect the PM Sensor (vehicle harness) harness connector.
5. Turn the ignition on, engine off.
6. Measure the voltage across the Fused Ignition (F205) Output circuit and the (Z908) Sensor Ground circuit at the PM Sensor (vehicle harness) harness connector.

   Does the voltage read between 10.7-16.0 volts?

   Yes 

   • Go To  9

   No 

   • Go To  8

1. Turn the ignition off.
2. Measure the resistance between ground and the (Z908) Sensor Ground circuit at the PM Sensor harness connector.

   Is the resistance above 3.0 Ohms?

   Yes 

   • Repair the (Z908) Sensor Ground circuit for an open/high resistance.
   • Perform the POWERTRAIN VERIFICATION TEST. Refer to 3.0L, POWERTRAIN VERIFICATION TEST .

   No 

   • Go To  9

1. The ignition must be off when checking a circuit for continuity to ground.
2. Isolate the circuit by disconnecting the PDC and every component harness connector containing the circuit being tested. Note:  Use the wiring diagram as a guide to follow the path of the circuit.
3. Connect the negative lead of the DVOM to a known good ground.
4. With the positive lead of the DVOM, probe the circuit being tested at the component harness connector and check for continuity between the circuit and ground.

Is there continuity between ground and the circuit being tested?

Yes 

• Repair the circuit for a short to ground. Use the wiring diagram as a guide to trace the circuit and look for any in-line connectors to help isolate the location of the short.
• Perform the POWERTRAIN VERIFICATION TEST. Refer to 3.0L, POWERTRAIN VERIFICATION TEST .

No 

• Go To  10

1. The ignition must be off when checking the continuity of a circuit.
2. Isolate the circuit by disconnecting the PDC and the component harness connector containing the circuit being tested. Note:  Use the wiring diagram as a guide to follow the path of the circuit.
3. Before measuring the resistance of any circuit, first measure the resistance between the two leads of the DVOM. Note:  The meter leads can add resistance to the measurement value.
4. Connect one lead of the DVOM to the circuit being tested at the component harness connector.
5. Connect the other lead of the DVOM to the circuit being tested at the PDC harness connector.

Is the resistance below 3.0 Ohms?

Yes 

• Go To  11

No 

• Repair the circuit for an open or high resistance.
• Perform the POWERTRAIN VERIFICATION TEST. Refer to 3.0L, POWERTRAIN VERIFICATION TEST .

1. Replace the Particulate Matter (PM) Sensor in accordance with the Service Information.
2. Connect the PM Sensor and PCM harness connectors.
3. Turn the ignition on.
4. With the scan tool, erase PCM DTCs.
5. Start the engine and run it until it reaches operating temperature.
6. With the scan tool, read DTCs.

   Did the DTC return?

   Yes 

   • Go To  12

   No 

   • Replacing the Particulate Matter (PM) Sensor repaired the condition.
   • Perform the POWERTRAIN VERIFICATION TEST. Refer to 3.0L, POWERTRAIN VERIFICATION TEST .

1. Disconnect all PCM harness connectors.
2. Disconnect all related in-line harness connections (if equipped).
3. Disconnect the related component harness connectors.
4. Inspect harness connectors, component connectors, and all male and female terminals for the following conditions:
   • Proper connector installation.
   • Damaged connector locks.
   • Corrosion.
   • Other signs of water intrusion.
   • Weather seal damage (if equipped).
   • Bent terminals.
   • Overheating due to a poor connection (terminal may be discolored due to excessive current draw).
   • Terminals that have been pushed back into the connector cavity.
   • Check for spread terminals and verify proper terminal tension.

   Repair any conditions that are found.

5. Connect all PCM harness connectors. Be certain that all harness connectors are fully seated and the connector locks are fully engaged.
6. Connect all in-line harness connectors (if equipped). Be certain that all connectors are fully seated and the connector locks are fully engaged.
7. Connect all related component harness connectors. Be certain that all connectors are fully seated and the connector locks are fully engaged.
8. With the scan tool, erase DTCs.
9. Test drive or operate the vehicle in accordance with the when monitored and set conditions.
10. With the scan tool, read DTCs.

    Did the DTC return?

    Yes 

    • Replace and program the Powertrain Control Module (PCM) in accordance with the Service Information.
    • Perform the POWERTRAIN VERIFICATION TEST. Refer to 3.0L, POWERTRAIN VERIFICATION TEST .

    No 

    • The wiring or poor connection problem has been repaired.
    • Perform the POWERTRAIN VERIFICATION TEST. Refer to 3.0L, POWERTRAIN VERIFICATION TEST .