Diagnostic Test

WARNING: This page is about a different car, the 2009 Jeep Liberty. However, it is still accessible from the selected car via links, so may be relevant.

CHECK FOR AN INTERNAL TRANSMISSION PROBLEM
1. This DTC is an informational DTC.
2. Check for any Service Information Tune-ups or Technical Service Bulletins that may apply.
3. This is usually a sign of Torque Converter Clutch failure or an internal transmission problem.
4. Check the Engine and Transmission Cooling Systems for proper operation.
  Repair
  - Repair internal Transmission, Torque Converter, and/or Transmission and Engine Cooling systems as necessary.
  - Perform the NAG1 TRANSMISSION VERIFICATION TEST. See DTC-Based Diagnostics/MODULE, Transmission Control (TCM) - Standard Procedure .