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Home >> Dodge and Ram >> 2024 >> ProMaster 1500 Base >> Repair and Diagnosis >> Engine Performance >> Testing & Diagnosis >> 3.6L - Pre-Diagnostic Troubleshooting Procedure, Intermittent Condition, Reprogramming And Verification Test >> Standard Procedure >> Intermittent Condition >> Diagnostic Test
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Diagnostic Test

INTERMITTENT CONDITION 

NOTE:

The conditions that set the DTC are not present at this time. Duplicating the conditions under which the stored DTC set is very important when diagnosing an intermittent condition. Review the scan tool Freeze Frame Data information and When Monitored conditions for the DTC being diagnosed. If possible, pay particular attention to the ambient air temperature when the DTC set. Electrical connections, such as wire terminal connections, solder joints, and printed circuit board traces will expand and contract due to temperature changes. If the DTC was set in extreme cold conditions, the vehicle may need to be tested in extreme cold conditions. 

NOTE:

Poor wire harness terminal connections are a big contributor to intermittent electrical connections. Follow the directions below to help identify the source of the intermittent electrical condition. 

  1. Record all DTCs on the repair order.
  2. Run a Vehicle Scan Report.
  3. Perform any Service Bulletins or PCM flash updates that may apply to the DTCs that are present.
  4. Use the scan tool to perform a System Test if one applies to a failing component.
    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.

  5. With the ignition on or engine running, monitor the scan tool parameters related to the DTC while wiggle testing the wiring harness. Look for parameter values to change and/or a DTC to set.
    NOTE:

    Using a data recorder and/or a lab scope may help diagnose intermittent conditions. 

  6. If numerous trouble codes were set, use a wire schematic and look for any common sensor supply or ground circuits.
  7. Perform a voltage drop test on the related circuits between the suspected inoperative component and the PCM.
  8. For Communication DTCs, perform the scan tool LOSS OF COMM TEST. This will force the modules on the CAN C bus to continuously ping each other every one second. Wiggle the applicable wires while reading the NUMBER OF NO RESPONSES. A value above 0 indicates the location of a circuit fault.
  9. Turn the ignition off.
  10. Visually inspect the related wire harness. Disconnect all of the related component and in-line harness connectors and check for the following:
    • Proper wiring harness routing.
    • Chafed, pierced, pinched, partially broken or open wiring harness insulation.
    • Wiring or wiring strands broken inside of the insulation.
    • Visually inspect the connector casings, locks, and weatherproof seals for any damage or water intrusion.
    • Visually inspect for broken, bent, pushed out, or corroded terminals.
    • Visually inspect the connectors and terminals for overheating due to a poor connection (terminals may be discolored due to excessive current draw).
    • Verify correct connector pin fit at the related connectors (drag test).
    • Connect all the related module, component and in-line wiring harness connectors and verify they are fully seated.
    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 the PCM Pinout Box and PCM Pinout Box Adapter to perform diagnosis.

  11. Inspect and clean all PCM, engine, and chassis grounds that are related to the DTCs that are present.
  12. For any Relay DTCs, actuate the Relay with the scan tool and wiggle the related wire harness to try to interrupt the actuation.
  13. For intermittent Evaporative Emission trouble codes perform a visual and physical inspection of the related parts including hoses and the Fuel Filler cap.
  14. For intermittent Misfire DTCs check for restrictions in the Intake and Exhaust systems, proper installation of sensors, vacuum leaks, and binding components that are run by the accessory drive belt.
  15. Check for any aftermarket accessories and verify they are installed and operate correctly. If needed, disconnect them to verify they are not the cause of the problem.

    Were any problems found during the above inspections?

    Yes 

    No 

    • Test Complete.
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