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Home >> Jeep >> 2017 >> Wrangler Sahara, Automatic Trans >> Repair and Diagnosis >> Transmission >> Automatic Trans >> (Transmission Control Module (TCM) - Electrical Diagnostics) >> DTC Troubleshooting >> U1512-Implausible Message Data Length Received From SCM >> Diagnostic Test
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Diagnostic Test

  1. CHECK FOR TIPM CAN BUS DTCS 
    1. With the scan tool, read TIPM DTCs.

      Are there any TIPM CAN BUS DTCs present?

      Yes 

      No 

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  2. ELECTRONIC SHIFT MODULE DTCS PRESENT 
    1. With the scan tool, read Steering Control Module (SCM) DTCs.

      Are there any SCM DTCs present?

      Yes 

      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 and program the TCM in accordance with the Service Information.
      • Perform TRANSMISSION VERIFICATION TEST. Refer to NAG1 TRANSMISSION VERIFICATION TEST .