Circuit DescriptionThe engine aftertreatment system monitors the soot load in the aftertreatment diesel particulate filter. Under normal operating conditions, the aftertreatment diesel particulate filter is self-cleaning, where soot is converted to carbon dioxide, nitrogen, and water. Under light load operating conditions, it can be necessary to perform a stationary regeneration of the aftertreatment diesel particulate filter. The soot load in the aftertreatment diesel particulate filter is estimated, using the aftertreatment differential pressure sensor and the calculated soot output of the engine.

Component LocationThe aftertreatment diesel particulate filter is located in the exhaust system and is installed by the original equipment manufacturer (OEM). Refer to the OEM service manual.

Conditions for Running the DiagnosticsThis diagnostic runs continuously when the engine is running.

Conditions for Setting the Fault CodesSoot accumulation within the diesel particulate filter occurred at a higher rate than under normal operating conditions.

Action Taken When the Fault Code is ActiveThe ECM illuminates the amber CHECK ENGINE lamp immediately when the diagnostic runs and fails.Conditions for Clearing the Fault CodeThe fault code status displayed by INSITE™ electronic service tool will change to INACTIVE immediately after the diagnostic runs and passes.

Shop TalkPossible causes of this fault code include:

Boost leaks in the charge-air cooler plumbingA malfunction of the variable geometry turbocharger (VGT)A malfunction of the exhaust gas recirculation (EGR) valveA malfunctioning in-range EGR differential pressure sensorA malfunctioning in-range boost pressure sensorA malfunctioning in-range barometric pressure sensorA cylinder misfire or overfueling.Reference the appropriate OEM wiring diagram when troubleshooting circuits that utilize wiring supplied by the OEM.

For intermittent power supply and datalink communication issues with Aftertreatment Components, it is highly recommended that the OEM Power Distribution Center fuses and relays be thoroughly checked for loose, missing or intermittent connections.

Possible Cause:1) Charge-air cooler failure2) Barometric pressure sensor failure3) Intake manifold pressure sensor failure4) Exhaust manifold pressure sensor failure5) Aftertreatment DPF differential pressure sensor failure6) Fuel rail pressure relief valve failure7) Loose injector high-pressure connector(s)8) High-pressure connector failure9) ECM calibration