Cummins ISB4.5 CM2150 Fault Code: 2198 PID: SID 027 SPN: 641 FMI: 11 VGT Actuator Driver Circuit – Root Cause Not Known. Intermittent communication between the smart VGT controller and the ECM has been detected.

Circuit Description
The variable geometry turbocharger (VGT) is electronically activated by the VGT actuator. The VGT actuator is a smart device and receives information via the J1939 data link from the primary engine control module (ECM). The VGT actuator performs its own diagnostics and reports malfunctions back to the primary engine ECM using the J1939 data link. The ECM then decodes the error message and converts it to a fault code.

Component Location
The VGT actuator is located on the turbocharger bearing housing.

Conditions for Running the Diagnostics
This diagnostic runs continuously when the keyswitch is in the ON position.

Conditions for Setting the Fault Codes
The VGT actuator does not receive a valid J1939 message from the ECM for 1 second.

Action Taken When the Fault Code is Active
-The ECM illuminates the amber CHECK ENGINE light immediately when the diagnostic runs and fails.
-The VGT will move to the default open position

Conditions for Clearing the Fault Code
The ECM will turn off the amber CHECK ENGINE light immediately after the VGT actuator receives a valid J1939 message from the ECM.

Shop Talk
Intermittent J1939 datalink connections or interference on the J1939 network are possible causes of this fault code. Also check for intermittent power supply and ground connections to the VGT actuator.