Circuit DescriptionThe exhaust gas recirculation (EGR) valve is controlled by a brushless motor located on top of the EGR valve. The EGR valve motor uses three different motor legs to move the valve through its range of motion. The ECM uses the EGR motor A, B, and C wires to command the EGR valve to the appropriate position in order to meet EGR flow targets.

The EGR valve motor contains three position sensors that detect the location of the EGR valve. These sensors report the position of the valve back to the ECM over the EGR valve position A, B, and C wires.

Component LocationThe ECM mounting location varies depending on engine model.

Conditions for Running the DiagnosticsThe diagnostic runs continuously when the keyswitch is turned ON.

Conditions for Setting the Fault CodesThe ECM detects that the temperature of the EGR valve driver internal to the ECM is greater than 170?C [338?F] for 70 seconds.

Action Taken When the Fault Code is ActiveThe ECM illuminates the amber CHECK ENGINE lamp and/or the Malfunction Indicator Lamp (MIL) immediately when the diagnostic runs and fails.Active and stationary regeneration of the diesel particulate filter will be disabled.The EGR valve will be closed.Engine torque will be reduced if the engine is operated for an extended period of time with this fault active.Conditions for Clearing the Fault CodeTo validate the repair, start the engine and let it idle for 2 minutes.The fault code status displayed by INSITE? electronic service tool will change to INACTIVE immediately after the diagnostic runs and passes.The ECM will turn off the amber CHECK ENGINE lamp after the diagnostic runs and passes.For On-Board Diagnostic (OBD) engines, the ECM will turn off the MIL after three consecutive trips where the diagnostic runs and passes.The Reset All Faults command in INSITE? electronic service tool can be used to clear active and inactive faults, as well as extinguish the MIL for OBD applications

Shop TalkThis fault code may be inactive when the vehicle is in the shop because the EGR valve driver temperature has cooled down. Therefore, troubleshoot multiple inactive counts of this fault code as an active fault code.

Possible causes of this fault code include:

Malfunctioning ECM.

Possible Cause:1) ECM failure2) ECM calibration