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Diagnostic Test

WARNING: This page is about a different car, the 2012 Dodge Durango. However, it is still accessible from the selected car via links, so may be relevant.
  1. CHECK FOR CAN C BUS COMMUNICATION DTCS 
    1. Using the scan tool, check for CAN DTCs.

      Is DTC U0001-CAN C BUS DTC or U0100-LOST COMMUNICATION WITH ECM/PCM set?

      Yes 

      No 

      • Go To  2.
  2. CHECK IF THE DTC IS CURRENT 
    NOTE:

    When the Transmission Control Module (TCM) detects and stores a DTC, the TCM also stores the vehicles operating conditions under which the DTC originally set. This information is located in the 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.

    1. Ignition on, engine not running.
    2. Using the scan tool, erase Transmission DTCs.
    3. Using the Environmental Data recorded earlier, try to duplicate the conditions in which the DTC originally set. It may be necessary to test drive the vehicle.
    4. Using the scan tool, read Transmission DTCs.

      Did the DTC U0103-LOST COMMUNICATION WITH ELECTRIC GEAR SHIFT MODULE 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 

      • Go To  3.
  3. CHECK THE WIRING AND CONNECTORS 
    1. The conditions necessary to set this DTC are not present at this time.
    2. Using the schematics as a guide, inspect the wiring and connectors specific to this circuit.
    3. Wiggle the wiring and connectors while checking for any possible open or shorted circuits.
    4. Check for any Service Information Tune-ups or Technical Service Bulletins that may apply.

      Were there any problems found?

      Yes 

      • Repair as necessary.
      • Refer to STANDARD PROCEDURE  and perform the NAG1 TRANSMISSION VERIFICATION TEST.

      No 

      • Test Complete.