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Home >> Jeep >> 2020 >> Compass Limited, FWD >> Repair and Diagnosis (Single Page) >> Transmission >> Automatic Trans >> (F21-250 Gen III Automatic Transmission - Electrical Diagnostics) >> DTC Troubleshooting >> P0602-00-Control Module Programming Error/Not Programmed >> Diagnostic Test
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Diagnostic Test

  1. CHECK FOR AN ACTIVE DTC 
    1. With the scan tool, read TCM DTCs and record on the repair order.
    2. Record the Event Data and Environmental Data.
    3. With the scan tool, erase DTCs.
    4. Using the recorded Event and Environmental Data, along with the When Monitored and Set Conditions above, operate the vehicle in the conditions that set the DTC.
    5. With the scan tool, read TCM DTCs.

      Did the DTC return?

      Yes 

      • Go to 2

      No 

  2. PROGRAM TRANSMISSION CONTROL MODULE (TCM) 
    1. Program the TCM. Refer to MODULE PROGRAMMING .
    2. Perform the TRANSMISSION VERIFICATION TEST. Refer to PRE-DIAGNOSTIC TROUBLESHOOTING PROCEDURE .

      Did the TCM program successfully?

      Yes 

      • Test complete.

      No 

      • Go to 3
  3. CHECK RELATED HARNESS CONNECTIONS 
    1. Disconnect all TCM 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.
      • Perform a terminal drag test on each connector terminal to verify proper terminal tension.

      Repair any conditions that are found.

    5. Reconnect all TCM harness connectors. Be certain that all harness connectors are fully seated and the connector locks are fully engaged.
    6. Reconnect all in-line harness connectors (if equipped). Be certain that all connectors are fully seated and the connector locks are fully engaged.
    7. Reconnect 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. Using the recorded Event and Environmental Data, along with the When Monitored and Set Conditions above, operate the vehicle in the conditions that set the DTC.
    10. With the scan tool, read TCM DTCs.

      Did the DTC return?

      Yes 

      No