CM2150 Electronic Control System – FAULT CODE 2635

VGT Actuator Driver Circuit – Condition Exists


Fault Code: 2635
PID: S027
SPN: 641
FMI: 11/31

VGT Actuator Driver Circuit – Condition Exists. A calibration mismatch between the VGT actuator and the ECM has been detected.

VGT actuation will be disabled.

ISB, ISC, and ISL – VGT Actuator Circuit

Circuit Description

The variable geometry turbocharger (VGT) is electronically activated by the VGT actuator. The VGT actuator is a smart device that receives information via the J1939 datalink from the primary engine electronic control module (ECM). The VGT actuator performs its own diagnostics and reports errors back to the primary engine ECM using the J1939 datalink.

Component Location

The VGT actuator is located on the turbocharger bearing housing. Refer to Procedure 100-002 (Engine Diagrams) in Section F for a detailed component location view.

Conditions for Running the Diagnostics

This diagnostic runs continuously when the keyswitch is in the ON position or when the engine is running.

Conditions for Setting the Fault Codes

  • The ECM has detected a calibration incompatibility between the VGT actuator and the ECM calibration.
  • The VGT actuator has detected that the system voltage is incorrect for the installed VGT actuator part number.
  • The ECM has detected an incorrect VGT actuator installed on the turbocharger.

Action Taken When the Fault Code is Active

  • The ECM illuminates the red STOP ENGINE light immediately when the diagnostic runs and fails.
  • VGT actuation will be disabled.

Conditions for Clearing the Fault Code

The diagnostic will clear at initial key-on if the error condition no longer exists. The ECM will turn off the red STOP ENGINE light and enable VGT operation immediately after the diagnostic runs and passes.

Shop Talk

Verify the electronic control module (ECM) calibration is correct. Check the calibration revision history found on QuickServe® Online for applicable fixes to the calibration stored in the ECM. If necessary, recalibrate the ECM.Refer to Procedure 019-032 (ECM Calibration Code) in Section 19.

This fault code is logged when the ECM has detected that an incorrect VGT actuator has been installed on the turbocharger.

Refer to Troubleshooting Fault Code t05-2635

Last Modified:  20-Jul-2010