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Home >> Jeep >> 2011 >> Grand Cherokee Overland, 3.6 G, AWD >> 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 CAN BUS DTCS ARE PRESENT 
    1. With the scan tool, check for CAN DTCs.

      Are there any CAN BUS DTCs present?

      Yes 

      • Refer to DTC Based Diagnostics and perform the appropriate diagnostic procedure.
      • Perform the NAG1 TRANSMISSION VERIFICATION TEST. Refer to NAG1 TRANSMISSION VERIFICATION TEST .

      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 DTC Based Diagnostics and perform the appropriate diagnostic procedure.
      • Perform the NAG1 TRANSMISSION VERIFICATION TEST. Refer to NAG1 TRANSMISSION VERIFICATION TEST .

      No 

      • 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.
      • Perform the NAG1 TRANSMISSION VERIFICATION TEST. Refer to NAG1 TRANSMISSION VERIFICATION TEST .