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Home >> Jeep >> 2009 >> Commander Sport, 4.7 P, 4WD >> Repair and Diagnosis >> External Pages >> Different variant/trim >> Section 5 (Transmission Control Module (TCM) - Electrical Diagnostics) >> DTC Troubleshooting >> P1644-Incorrect Variant/Configuration >> Diagnostic Test
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Diagnostic Test

WARNING: This page is about a different variant/trim than selected.
  1. PERFORM TCM REPLACEMENT PROCEDURE 
    NOTE: Controller is programmed with generic software and will not allow the correct vehicle Powertrain management.
    1. With the scan tool, perform the TCM replacement procedure.

      Were you able to update the controller successfully?

      Yes 

      No 

      • Using the schematics as a guide, check the Transmission Control Module (TCM) pins, terminals, and connectors for corrosion, damage, or terminal push out. Pay particular attention to all power and ground circuits. If no problems are found, replace the TCM in accordance with the Service Information.
      • Perform NAG1 TRANSMISSION VERIFICATION TEST. See DTC-Based Diagnostics/MODULE, Transmission Control (TCM) - Standard Procedure