Cummins ISB4.5 CM2150 Fault Code: 1993 PID: SPN: 4795 FMI: 31 Aftertreatment Diesel Particulate Filter Missing – Condition Exists.

Circuit Description
The engine aftertreatment system monitors for the presence of the aftertreatment diesel particulate filter. This diagnostic checks to make sure that the aftertreatment diesel particulate filter is present and functioning correctly.

Component Location
The aftertreatment 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 Diagnostics
This diagnostic runs when the engine is running and exhaust flow is above a minimum level.

Conditions for Setting the Fault Codes
This diagnostic monitors the aftertreatment diesel particulate filter differential pressure sensor. When the differential pressure is below a minimum value and exhaust flow rate is above a minimum flow rate, the fault code is set.

Action Taken When the Fault Code is Active
-The ECM will illuminate the amber CHECK ENGINE lamp immediately after the diagnostic runs and passes for two consecutive trips.

Conditions for Clearing the Fault Code
-To validate the repair, start the engine and operate it at high idle. It is necessary to elevate the exhaust flow for at least 3 minutes to clear this fault code. For certain applications, it may be necessary to drive the vehicle in order to achieve adequate exhaust flow.
-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.
-The “Reset All Faults” command in INSITE™ electronic service tool can be used to clear active and inactive faults.

Possible Causes
-The aftertreatment diesel particulate filter has been removed from the vehicle
-The aftertreatment diesel particulate filter is cracked or broken
-The aftertreatment diesel particulate filter differential tubes are installed incorrectly, broken, loose, or have been tampered with
-The aftertreatment diesel particulate filter differential tubes are installed backward.

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.