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Diagnostic Test

  1. CHECK FOR AN ACTIVE DTC 
    1. Start the engine and allow it to reach operating temperature.
      WARNING:

      When the engine is operating, do not stand in direct line with the fan. Do not put your hands near the pulleys, belts or fan. Do not wear loose clothing. Failure to follow these instructions may result in possible serious or fatal injury.

      NOTE:

      It may be necessary to test drive the vehicle within the DTC monitoring conditions in order for this DTC to set.

    2. With the scan tool, read DTCs and record on the repair order.

      Is the DTC active or pending?

      Yes 

      • Go To  2

      No 

  2. CHECKING THE EXHAUST SYSTEM FOR LEAKS 
    1. Turn the ignition off.
    2. Perform the CHECKING THE EXHAUST SYSTEM FOR LEAKS diagnostic procedure. Refer to CHECKING THE EXHAUST SYSTEM FOR LEAKS .

      Were any problems found?

      Yes 

      No 

      • Go To  3
  3. CHECK THE FUEL SYSTEM 
    1. Check the entire fuel system for high fuel pressure, excessive fuel volume, or leaking Fuel Injectors. Refer to DIAGNOSIS AND TESTING .

      Were any problems found?

      Yes 

      No 

      • Go To  4
  4. CHECK THE OXYGEN SENSOR OPERATION 
    NOTE:

    Check for signs of contaminants that may have damaged the O2 Sensor, such as contaminated fuel, unapproved silicone, oil and coolant.

    1. Perform the diagnostic procedure for CHECKING THE OXYGEN SENSOR OPERATION. Refer to CHECKING THE OXYGEN SENSOR OPERATION .

      Were any problems found?

      Yes 

      No 

      • Go To  5
  5. CHECK RELATED HARNESS CONNECTIONS 
    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 

      No