Cummins ISX11.9 CM2250 (2010-12) Fault Code: 2639 (X) 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 DPF. Under normal operating conditions, the aftertreatment DPF 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 DPF. The soot load in the aftertreatment DPF is estimated, using the aftertreatment differential pressure sensor and the calculated soot output of the engine.

This fault code can be triggered if the application is not operating at a duty cycle high enough to regenerate the aftertreatment DPF. This fault code indicates that the exhaust temperatures exiting the turbocharger are not high enough to actively regenerate the soot that is trapped in the aftertreatment DPF. It may be necessary to increase the duty cycle of the application in order to prevent plugging of the aftertreatment DPF.

Component Location
The aftertreatment diesel particulate filter is located in the exhaust system and is installed by the original equipment manufacturer. Refer to the equipment manufacturer service information.

Conditions for Running the Diagnostics
This diagnostic runs continuously when engine speed is greater than 500 rpm.

Conditions for Setting the Fault Codes
The engine control module (ECM) detects that the soot load of the aftertreatment DPF has reached the first stage of plugging.

Action Taken When the Fault Code is Active
The ECM will illuminate the aftertreatment DPF 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 DPF increases.
Conditions for Clearing the Fault Code
After completing a stationary regeneration (as instructed in this fault code troubleshooting tree) and no additional fault codes become active, the repair has been validated.
The fault code status displayed by INSITE? electronic service tool will change to INACTIVE immediately after the soot load in the aftertreatment DPF has dropped below the least severe level and the diagnostic runs and passes.
The ECM will turn off the aftertreatment DPF 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 fault codes.

Shop Talk
Note: Repeated occurrences of this fault code may indicate the engine requires frequent regeneration. Refer to the Aftertreatment Diesel Particulate Filter-Excessive Automatic and/or Stationary Regeneration troubleshooting symptom tree in Section TS 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 DPF.
Possible engine damage that causes excessive black smoke to be generated.
Excessive ash in the DPF.
The aftertreatment diesel particulate filter soot loading can be classified into four different stages. As the soot load increases, the AFTERTREATMENT lamp and the Cummins? CHECK ENGINE (Amber) or STOP ENGINE (Red) lamp will operate according to the table below. The stationary regeneration procedure can be used to clear the soot from the aftertreatment DPF in stages 1, 2, and 3. At level 4, the aftertreatment DPF is completely plugged and must be replaced. Inadequate exhaust temperatures entering the aftertreatment system can be a cause of high soot loads in the aftertreatment DPF. The duty cycle of the application may need to be increased in order to prevent excessive soot from accumulating in the filter.

Soot Level Stage Cummins? Fault Code Aftertreatment Diesel Particulate Filter Lamp Status Cummins? Lamp Status Service Procedure Engine Protection Strategy
1 2639 Solid Off Perform stationary regeneration procedure No engine protection derate
2 2639 Flashing Off Perform stationary regeneration procedure Mild engine torque derate
3 1921 Flashing Amber Perform stationary regeneration procedure Moderate engine torque and engine speed derate
4 1922 Off Red Inspect and clean or replace aftertreatment DPF Severe engine torque and engine speed derate

Reference the appropriate equipment manufacturer wiring diagram when troubleshooting circuits that utilize wiring supplied by the equipment manufacturer.

For intermittent power supply and datalink communication issues with aftertreatment components, it is highly recommended that the equipment manufacturer power distribution center fuses and relays be thoroughly checked for loose, missing, or intermittent connections.

Possible Cause:
1) N/A