SPN 641 fault code means Engine Variable Geometry Turbocharger Actuator #1 has a problem.
Details for each FMI code:
- 7 – Mechanical System Not Responding Or Out Of Adjustment
- 9 – Abnormal Update Rate, communication lost.
- 11 – Actuator #1 Root Cause Not Known
- 12 – Actuator #1 Bad Intelligent Device Or Component
- 13 – Actuator #1 Out Of Calibration
- 15 – Actuator #1 Data Valid But Above Normal Operating Range – Least Severe Level
- 31 – Condition Exists, Internal error, problem unknown.
Suggested things to do:
Verify ECM calibration. Check turbocharger actuator and connections.