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Home >> Jeep >> 2016 >> Wrangler Rubicon, Automatic Trans >> Repair and Diagnosis >> Transmission >> Transmission Control Systems >> (Transmission Control Module (TCM) - Electrical Diagnostics) >> DTC Troubleshooting >> U1601-Ecu Application Software Code 1 Missing Or Corrupted >> Diagnostic Test
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Diagnostic Test

  1. CHECK FOR ACTIVE DTC U1601 
    NOTE:

    This DTC must be active for the results of this test to be valid. Check for a loose scan tool connection. Verify battery charger is installed and charge rate provides approximately 13.5 volts.

    1. Turn the Ignition ON, Engine not running.
    2. With the scan tool, read the DTCs.
    3. With the scan tool, follow the reprogramming procedure and reflash the Transmission Control Module (TCM) while maintaining voltage as noted above.
    4. With the scan tool, read the DTCs.

      Does the scan tool display DTC U1601?

      Yes 

      • 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 MODULE, TRANSMISSION CONTROL .
      • Perform the TRANSMISSION VERIFICATION TEST.

        Refer to STANDARD PROCEDURE .

      No 

      • Go to  2
  2. CHECK WIRING AND CONNECTORS 
    1. The conditions necessary to set the 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 wires while checking for shorted and open circuits.
    4. Check for any Service Bulletins that may apply.

      Were there any problems found?

      Yes 

      • Repair as necessary.
      • Perform the TRANSMISSION VERIFICATION TEST.

        Refer to STANDARD PROCEDURE .

      No 

      • Test complete.