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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 >> U0401-Implausible Data Received From ECM/Pcm >> Diagnostic Test
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Diagnostic Test

  1. CHECK IF TIPM CAN BUS DTCS ARE PRESENT 
    1. With the scan tool, read TIPM DTCs.

      Are there any TIPM CAN BUS DTCs present?

      Yes 

      No 

      • Go To  2
  2. CHECK IF ENGINE DTCS ARE PRESENT 
    1. With the scan tool, read Engine DTCs.

      Are there any Engine DTCs present?

      Yes 

      • Refer to the DTC INDEX article and perform the appropriate diagnostic procedure.
      • Perform NAG1 TRANSMISSION VERIFICATION TEST. Refer to STANDARD PROCEDURE .

      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 MODULE, TRANSMISSION CONTROL .
      • Perform NAG1 TRANSMISSION VERIFICATION TEST. Refer to STANDARD PROCEDURE .