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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 

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

      Are there any HVAC DTCs present?

      Yes 

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

      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 STANDARD PROCEDURE  and perform the NAG1 TRANSMISSION VERIFICATION TEST.