Cummins X15 CM2450 X124B (2018 & Newer) Fault Code: 2639 PID: SID 324 SPN: 3251 FMI: 15 Aftertreatment Diesel Particulate Filter Differential Pressure- Data Valid But Above Normal Operating Range- Least Severe Level

Circuit Description
The 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 Location
The 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 Diagnostics
This diagnostic runs continuously when the engine is running.

Conditions for Setting the Fault Codes
The Engine Control Module (ECM) detected the soot load of the aftertreatment diesel particulate filter had reached the first stage of plugging.

Action Taken When the Fault Code is Active
The ECM will illuminate the aftertreatment diesel particulate filter lamp immediately after the diagnostic is set.
The ECM will flash the aftertreatment dash lamp as the severity of the soot load increases.
Torque output of the engine will be reduced as the soot load in the aftertreatment diesel particulate filter increases.
Conditions for Clearing the Fault Code
After completing a stationary regeneration (as instructed in this fault code troubleshooting tree) and no additional faults become active, the repair has been validated.

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 aftertreatment diesel particulate filter lamp immediately 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, as well as extinguish the MIL for OBD applications.

Shop Talk
Note: This fault code indicates that the aftertreatment diesel particulate filter requires maintenance by performing a stationary regeneration procedure. This is a maintenance procedure only and is not covered by Cummins Inc. warranty.

Note: Repeated occurrences of this fault code may indicate the engine requires frequent regeneration. Refer to symptom tree t147 (Aftertreatment Diesel Particulate Filter-Excessive Automatic and/or Stationary Regeneration) to identify the cause of frequent regeneration.

Possible causes of this fault code include:

The engine has been operating in light load operating conditions that prevent exhaust temperatures from being high enough to regenerate the aftertreatment diesel particulate filter
Possible engine damage that causes excessive black smoke to be generated.

Possible Cause:
1) ECM calibration