Circuit DescriptionThe aftertreatment fuel pressure sensor is used to monitor the fuel pressure into the aftertreatment system. The electronic control module (ECM) supplies the aftertreatment fuel pressure sensor a 5 volt reference voltage.

Component LocationThe aftertreatment fuel pressure sensor is located in the aftertreatment fuel shutoff manifold.

Conditions for Running the DiagnosticsThis diagnostic runs during active regeneration of the aftertreatment diesel particulate filter.

Conditions for Setting the Fault CodesThe aftertreatment fuel pressure is less than 300 kPa [43.5 psi] for more than 15 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 regeneration of the aftertreatment diesel particulate filter will be disabled until the next key cycle.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, perform INSITE? electronic service tool Aftertreatment Diesel Particulate Filter Regeneration Test. Once the temperatures in the aftertreatment system are warm enough to inject diesel fuel into the exhaust, the diagnostic will run.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 Diagnostics (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 TalkPossible causes of this fault code include:

Plugged or restricted aftertreatment fuel supply linePlugged or restricted aftertreatment fuel shutoff manifoldPlugged or restricted pressure side fuel filterMalfunctioning fuel pump gear pump.

Possible Cause:1) ECM calibration