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Home >> Jeep >> 2021 >> Cherokee Altitude, FWD >> Repair and Diagnosis >> Engine Performance >> System >> 2.4L - DTCS P1048 To P1D73 >> DTC Troubleshooting >> P1609-Internal Control Module Engine Oil Temperature Performance >> Diagnostic Test
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Diagnostic Test

  1. CHECK FOR AN ACTIVE DTC 
    1. Turn the ignition on.
    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. CHECK FOR OTHER DTCS 
    1. Refer to the recorded DTCs.

      Are there any other PCM DTCs active or pending?

      Yes 

      No 

      • Go To  3
  3. CHECK THE POWERTRAIN CONTROL MODULE FOR PROPER SOFTWARE LEVEL 
    1. Turn the ignition on.
    2. Verify the PCM is at the latest calibration (flash level).

      Is there an update for the PCM?

      Yes 

      • Go To  4

      No 

      • Go To  5
  4. PROGRAM THE POWERTRAIN CONTROL MODULE 
    1. Update the PCM in accordance with the Service Information. Refer to MODULE, POWERTRAIN CONTROL (PCM), MODULE PROGRAMMING .
    2. Cycle the ignition off and on.
    3. With a scan tool, read DTCs.

      Does this DTC reset by itself?

      Yes 

      • Go To  5

      No 

  5. CHECK RELATED PCM AND COMPONENT CONNECTIONS 
    1. Perform any Service Bulletins that apply.
    2. Disconnect all PCM harness connectors.
    3. Disconnect all related in-line harness connections (if equipped).
    4. Disconnect the related component harness connectors.
    5. 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.

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

      Did the DTC return?

      Yes 

      No 

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