LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Dodge and Ram >> 2012 >> Challenger SXT Plus >> Repair and Diagnosis >> External Pages >> Different car >> Section 50 (Transmission Control Module (TCM) - Electrical Diagnostics) >> DTC Troubleshooting >> P1644-Incorrect Variant/Configuration >> Diagnostic Test
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Diagnostic Test

WARNING: This page is about a different car, the 2012 Jeep Wrangler. However, it is still accessible from the selected car via links, so may be relevant.
  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 

      • Test Complete.
      • Refer to STANDARD PROCEDURE  and perform the NAG1 TRANSMISSION VERIFICATION TEST.

      No 

      • Using the schematics as a guide, check the Transmission Control Module (TCM) terminals 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.
      • Refer to STANDARD PROCEDURE  and perform the NAG1 TRANSMISSION VERIFICATION TEST.