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Home >> Jeep >> 2021 >> Compass Trailhawk >> Repair and Diagnosis >> Engine Performance >> System >> 2.4L - DTCS P1048 To P1D68 >> DTC Troubleshooting >> P1609-Internal Control Module Engine Oil Temperature Performance >> Diagnostic Test
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Diagnostic Test

  1. CHECK FOR AN ACTIVE DTC 
    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.

    1. Turn the ignition on.
    2. With the scan tool, erase DTCs in the Powertrain Control Module (PCM).
    3. Start the engine and allow it to reach operating temperature.
    4. Increase engine speed by pressing the accelerator pedal. Do not exceed 3500 rpm.
    5. With the scan tool, read DTCs.

      Is the DTC active or pending?

      Yes 

      • Go To  2

      No 

  2. CHECK FOR OTHER DTCS 
    1. Refer to the recorded DTCs.

      Are there any other DTCs active or pending?

      Yes 

      • Perform the applicable diagnostic procedure(s). Refer to appropriate diagnostic information .

      No 

      • Go To  3
  3. CHECK FOR PCM SOFTWARE UPDATE 
    1. With the scan tool, read and record the PCM part number.
    2. Verify the Powertrain Control Module (PCM) is at the latest calibration (flash level). If not at the latest flash level, update the Powertrain Control Module (PCM) in accordance with the Service Information. Refer to appropriate diagnostic information .
      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.

    3. Turn the ignition on.
    4. With the scan tool, erase DTCs in the PCM.
    5. Start the engine and allow it to idle.
    6. Operate the accelerator pedal by gradually tipping in and out of the throttle and performing various throttle maneuvers. Do not exceed 3500 rpm.
    7. With the scan tool, read DTCs.

      Did the DTC return?

      Yes 

      • Go To  4

      No 

  4. 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