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Home >> Dodge and Ram >> 2012 >> Challenger SXT Plus >> Repair and Diagnosis >> Transmission >> Transmission Control Systems >> (Transmission Control Module (TCM) - Electrical Diagnostics) >> DTC Troubleshooting >> U0164-Lost Communication With HVAC Control Module >> Diagnostic Test
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Diagnostic Test

  1. CHECK THE TIPM FOR CAN C BUS COMMUNICATION DTCS 
    1. With the scan tool, check for TIPM DTCs.

      Does the TIPM report the DTC U0001-CAN C BUS DTC or U0164-LOST COMMUNICATION WITH HVAC CONTROL MODULE?

      Yes 

      • Refer to U0001-CAN C BUS and perform the diagnostic procedure first if it is present.
      • Refer to STANDARD PROCEDURE  and perform the NAG1 TRANSMISSION VERIFICATION TEST.

      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. With 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. With the scan tool, read Transmission DTCs.

      Did the DTC U0164-LOST COMMUNICATION WITH HVAC CONTROL MODULE reset?

      Yes 

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

      No 

      • Go To  3.
  3. INTERMITTENT 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.