CM871 and CM876 Electronic Control Systems, ISX and ISM Engines – FAULT CODE 1922

Aftertreatment Diesel Particulate Filter Differential Pressure – Data Valid but Above Normal Operational Range – Most Severe Level


Overview

CODE REASON EFFECT
Fault Code: 1922
PID: S324
SPN: 3251
FMI: 0/0
LAMP: Red
SRT: 

Aftertreatment Diesel Particulate Filter Differential Pressure – Data Valid but Above Normal Operational Range – Most Severe Level. The soot load of the aftertreatment diesel particulate filter has exceeded the recommended limits.

The stop engine light will illuminate. Severe engine derate.

ISX and ISM – Aftertreatment System
SMALL | MEDIUM | LARGE

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.

This fault code can be triggered if the application is not operating at a duty cycle that is high enough to actively regenerate the aftertreatment diesel particulate filter. 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 diesel particulate filter. It can be necessary to increase the duty cycle of the application in order to prevent plugging of the aftertreatment diesel particulate filter.

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 speed is greater than 500 rpm.

Conditions for Setting the Fault Codes

This fault code indicates that the soot load inside the aftertreatment diesel particulate filter has reached the maximum level: soot level stage 4.

Action Taken When the Fault Code is Active

  • The ECM will illuminate the red STOP ENGINE light immediately after the diagnostic runs and fails.
  • Active and stationary (parked) regeneration of the diesel particulate filter will be disabled.
  • A severe torque derate will be applied to the output of the engine (Note: There is no derate in emergency vehicle calibrations).

Conditions for Clearing the Fault Code

  • Clean or replace the aftertreatment diesel particulate filter.
  • Use INSITE™ electronic service tool to perform the Diesel Particulate Filter Reset procedure found under the Aftertreatment Maintenance section of Advanced ECM Data.
  • Use INSITE™ electronic service tool to perform the Aftertreatment Diesel Particulate Filter Regeneration test found in the ECM Diagnostics Test.

The ECM will turn off the red STOP ENGINE light immediately after the soot load in the aftertreatment diesel particulate filter has dropped below the most severe level.

Shop Talk

Verify the electronic control module (ECM) calibration is correct. Check the calibration revision history found on QuickServe™ Online for applicable fixes to the calibration stored in the ECM. If necessary, calibrate the ECM. Refer to Procedure 019-032 in Section 19.

This fault code indicates that the soot load inside the aftertreatment diesel particulate filter has reached the maximum level, soot level stage 4. Regeneration of the aftertreatment diesel particulate filter at this stage is not possible. The aftertreatment diesel particulate filter must be inspected. If it meets the inspection criteria, it can be cleaned using an SPX air pulse cleaning machine (or equivalent machine). If it does not meet the inspection criteria, it must be replaced.

Possible causes of this fault code include:

  • The engine has been operating in a light load condition that prevents exhaust temperatures from being high enough to actively regenerate the aftertreatment diesel particulate filter.
  • Possible base engine damage that causes excessive black soot to be generated.

The aftertreatment diesel particulate filter soot loading can be classified into four different stages. As the soot load increases, the aftertreatment diesel particulate filter lamp and the Cummins® CHECK ENGINE (Amber) or STOP ENGINE (Red) lamp will operate according to the table below. Inadequate exhaust temperatures entering the aftertreatment system can be a cause of high soot loads in the aftertreatment diesel particulate filter. 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 diesel particulate filter
Severe engine torque and engine speed derate

Refer to Troubleshooting Fault Code t05-1922

Last Modified:  09-Jul-2010