Diagnostic Test

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 .