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Home >> Dodge and Ram >> 2012 >> Durango R/T, RWD >> Repair and Diagnosis >> External Pages >> Different variant/trim >> Section 5 ((Transmission Control Module (TCM) - Electrical Diagnostics)) >> DTC Troubleshooting >> P2638-Torque Management Feedback Signal Performance >> Diagnostic Test
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Diagnostic Test

WARNING: This page is about a different variant/trim than selected.
  1. CHECK FOR ENGINE DTC PRESENT 
    1. With the scan tool, check engine DTCs.

      Are there any engine DTCs present?

      Yes 

      No 

      • Go To  2.
  2. CHECK FOR CAN BUS DTCS 
    1. With the scan tool, check for any CAN bus DTCs or a sign of a CAN bus failure.

      Are there any CAN bus DTCs present in any module other than the TCM or an overall indication of a CAN bus communication problem?

      Yes 

      • This is an indication of a CAN bus communication problem. Depending on the DTC, refer to the module reporting the DTC and perform diagnostics for the appropriate symptom.
      • Refer to STANDARD PROCEDURE  and perform the NAG1 TRANSMISSION VERIFICATION TEST.

      No 

      • Go To  3.
  3. CHECK IF DTC RESETS 
    1. Turn the ignition off to the lock position.
    2. Replace and program the Powertrain Control Module in accordance with the Service Information. Refer to STANDARD PROCEDURE for the appropriate service procedure.
    3. With the scan tool, record the Environmental Data and erase Transmission DTCs.
      NOTE:

      If the TCM detects and stores a DTC, the TCM also stores the vehicles operating conditions under which the DTC originally set and is located in scan tool under Environmental Data. Before erasing any stored DTCs, record any available data to assist in duplicating the conditions in which the DTC originally set.

    4. Using the Environmental Data recorded earlier, test drive the vehicle while trying to duplicate the conditions in which the DTC originally set.
    5. With the scan tool, read Transmission DTCs.

      Did the DTC P2638-TORQUE MANAGEMENT FEEDBACK SIGNAL PERFORMANCE reset?

      Yes 

      • 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 and program the TCM in accordance with the Service Information. Refer to MODULE, TRANSMISSION CONTROL, REMOVAL .
      • Refer to STANDARD PROCEDURE  and perform the NAG1 TRANSMISSION VERIFICATION TEST.

      No 

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