Paccar

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, recalibrate the ECM.

Possible causes:

1)Open return circuit in the harness, connectors, or sensor
2)Signal circuit shorted to sensor supply or battery voltage.

Possible repairs:

1)Replace the aftertreatment diesel particulate filter differential pressure sensor.
2)Repair or replace the OEM harness.

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, recalibrate the ECM.

Possible causes:

1)Signal circuit open or shorted to ground in the engine harness or sensor
2)Supply line open or shorted to ground.

Possible reapirs:

1)Replace the aftertreatment diesel particulate filter differential pressure sensor.
2)The removal and installation of the connector may correct the fault.
3)Repair or replace the OEM harness.

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.

Possible causes:

1)Stuck in-range aftertreatment diesel particulate filter differential pressure sensor reading
2)High resistance in the aftertreatment diesel particulate filter differential pressure sensor signal or return wires
3)Plugged aftertreatment differential pressure sensor ports could cause this fault code if pressure is held in the port after the engine is turned off.

Possible reapirs:

1)Replace the aftertreatment diesel particulate filter differential pressure sensor.
2)Repair or replace the OEM harness.
3)Replace the ECM.v

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, recalibrate the ECM.

When the keyswitch is initially turned on and at various times during engine operation, the closed position of the EGR valve is checked. This diagnostic checks to make sure the EGR valve is not stuck open.

This fault code is logged when the following error conditions exist:

1)The EGR valve motor measures the position of the EGR valve at initial key-on. If the valve is detected to be out of the normal position, this fault code will be logged.
2)The EGR valve will close when the fault code is active.
3)The fault code will remain active until the next key cycle.

The fault code will only go inactive if the initial key-on EGR position check passes.

The aftertreatment system must be inspected after making the appropriate repair outlined in this fault code troubleshooting tree. Progressive damage to the aftertreatment system may have occurred. Perform the Snap-Acceleration Test to check for a malfunctioning diesel particulate filter.

Possible repairs:

1)Replace the EGR valve assembly.

Verify the 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.

This diagnostic checks the EGR differential pressure sensor reading when the EGR valve is open. Since the EGR valve is open, the reading of the EGR differential pressure must be greater than zero. If the ECM detects a reading lower than expected with the EGR valve open, this fault code is logged.

Possible causes:

1)A malfunctioning EGR differential pressure sensor
2)A stuck closed EGR valve
3)EGR differential pressure sensor flow port cross-drillings are plugged with soot or shellac
4)A fouled EGR cooler.

Possible repairs:

1)Clean the EGR differential pressure sensor flow ports.
2)Clean the EGR cooler.
3)Replace the EGR delta pressure sensor.
4)Repair or replace the engine harness.
5)Replace the ECM.

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.
Fault Code 1911 is activated when the sensed rail fuel pressure reaches the opening pressure of the rail fuel pressure relief valve. Sensed pressure has exceeded system target range.

In normal engine operation, the ECM calibration varies the flow commanded to the fuel pump actuator to achieve the correct fuel rail pressure. System failures that cause loss of pressure control can cause the fuel rail pressure relief valve to open. The fuel rail pressure relief valve acts to protect the high-pressure components from over-pressurization. If the ECM detects that the fuel rail pressure relief valve is open without detection of a fuel pump actuator circuit error, Fault Code 1911 will become active. On certain applications, the ECM will attempt to reset automatically causing a momentary loss of power for less than 1 second.

Conditions that can cause Fault Code 1911:

1)Purging air through the fuel system can cause a pressure overshoot, therefore causing Fault Code 1911 to log. A few bubbles exiting the line during the air in fuel test is expected. A foamy appearance is an indication of a leak that allows air to enter, a severe inlet restriction that causes cavitation, or a system that is not yet primed.
2)Sustained periods of very low pressure under load followed by pressure recovery overshoot. This can be caused by high restriction due to plugged filters (Fault Code 559).
3)A tampered fuel pressure sensor that reads low, a biased pressure sensor, or a poor electrical connection.
4)If an intermittent electrical circuit problem with the fuel pump actuator circuit exists, it is possible for Fault Code 1911 to become active, then inactive during normal engine operation. ECM Fault Code 2311 is designed to detect electrical circuit issues with the actuator. Therefore, it is only necessary to inspect for bad connectors or harness issues for Fault Code 1911 if no other fault codes exist. An electric fuel control actuator with excessive leakage will result in high rail fuel pressures at idle or light load.
5)Other conditions include ECM wiring harness issues such as poor grounds, battery voltage spikes, electrical noise, low alternator output, and large disturbances of battery voltage, as when jump-starting the vehicle.
6)The fuel rail pressure sensor should also be checked. When checking the fuel rail pressure sensor accuracy, make sure the high-pressure fuel rail is not pressurized. The fuel pump, high-pressure fuel lines, and fuel rail contain very high-pressure fuel. Do not loosen any fittings while the engine is running. Wait at least 10 minutes after shutting down the engine before loosening any fittings in the high-pressure fuel system to allow pressure to decrease to a lower level. There could be a significant amount of time waiting on the rail to depressurize to zero on some engines. In such cases, it may be necessary to manually relieve the pressure from the high-pressure fuel rail.

Possible repairs:

1)Replace the rail fuel pressure sensor.
2)If no issues are found, replace the suction side fuel filter and prime the fuel system.
3)If the pump meets specifications, replace the fuel filter and prime the fuel system.
4)Repair the source of the high fuel drain line restriction.
5)Replace the fuel pump actuator.

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.
Fault Code 1911 is activated when the sensed rail fuel pressure reaches the opening pressure of the rail fuel pressure relief valve. Sensed pressure has exceeded system target range.

In normal engine operation, the ECM calibration varies the flow commanded to the fuel pump actuator to achieve the correct fuel rail pressure. System failures that cause loss of pressure control can cause the fuel rail pressure relief valve to open. The fuel rail pressure relief valve acts to protect the high-pressure components from over-pressurization. If the ECM detects that the fuel rail pressure relief valve is open without detection of a fuel pump actuator circuit error, Fault Code 1911 will become active. On certain applications, the ECM will attempt to reset automatically causing a momentary loss of power for less than 1 second.

Conditions that can cause Fault Code 1911:

1)Purging air through the fuel system can cause a pressure overshoot, therefore causing Fault Code 1911 to log. A few bubbles exiting the line during the air in fuel test is expected. A foamy appearance is an indication of a leak that allows air to enter, a severe inlet restriction that causes cavitation, or a system that is not yet primed.
2)Sustained periods of very low pressure under load followed by pressure recovery overshoot. This can be caused by high restriction due to plugged filters (Fault Code 559).
3)A tampered fuel pressure sensor that reads low, a biased pressure sensor, or a poor electrical connection.
4)If an intermittent electrical circuit problem with the fuel pump actuator circuit exists, it is possible for Fault Code 1911 to become active, then inactive during normal engine operation. ECM Fault Code 2311 is designed to detect electrical circuit issues with the actuator. Therefore, it is only necessary to inspect for bad connectors or harness issues for Fault Code 1911 if no other fault codes exist. An electric fuel control actuator with excessive leakage will result in high rail fuel pressures at idle or light load.
5)Other conditions include ECM wiring harness issues such as poor grounds, battery voltage spikes, electrical noise, low alternator output, and large disturbances of battery voltage, as when jump-starting the vehicle.
6)The fuel rail pressure sensor should also be checked. When checking the fuel rail pressure sensor accuracy, make sure the high-pressure fuel rail is not pressurized. The fuel pump, high-pressure fuel lines, and fuel rail contain very high-pressure fuel. Do not loosen any fittings while the engine is running. Wait at least 10 minutes after shutting down the engine before loosening any fittings in the high-pressure fuel system to allow pressure to decrease to a lower level. There could be a significant amount of time waiting on the rail to depressurize to zero on some engines. In such cases, it may be necessary to manually relieve the pressure from the high-pressure fuel rail.

Possible repairs:

1)Replace the rail fuel pressure sensor.
2)Replace the fuel pump actuator. Use the following procedure for the correct tightening sequence.
3)Repair missing or degraded ground connections.

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.

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:

1)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.
2)Possible engine failure that causes excessive black soot to be generated.
3)If Fault Code 2777 is active along with Fault Code 1921, this indicates that a regeneration inhibit message has been received by the engine ECM and that active regeneration of the aftertreatment diesel particulate filter was not permitted. Confirm that the OEM settings for the aftertreatment permit switch are configured correctly.
4)The aftertreatment diesel particulate filter can accumulate an excessive amount of ash in a short time period, due to excessive oil consumption or due to non-combustible elements such as, but not limited to, iron, potassium, or calcium contained in the fuel supply or additives.
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 temperature of the exhaust gases entering the aftertreatment system can be a cause of high soot loads in the aftertreatment diesel particulate filter. The duty cycle of the application will need to be increased in order to prevent excessive soot from accumulating in the filter.

Possible repairs:

1)Change the duty cycle of the application in order to increase the exhaust temperatures entering the aftertreatment system.

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.

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, or equivalent, cleaning machine. If it does not meet the inspection criteria, it must be replaced.

If Fault Code 1922 is active at the same time as Fault Code 1981, it is necessary to clear Fault Code 1981 by following the troubleshooting tree for that fault, then referencing the steps for troubleshooting and clearing Fault Code 1922, below.

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:

1)The aftertreatment wiring harness connectors may be connected to the wrong aftertreatment temperature sensors.
2)The aftertreatment wiring harness or aftertreatment temperature sensor connector pin installation may be incorrect.
3)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.
4)A possible base engine malfunction that causes excessive black soot to be generated.
5)If both Fault Code 1921 and 2777 are inactive with an active Fault Code 1922, this indicates that a regeneration inhibit message had been received by the engine ECM and that active regeneration of the aftertreatment diesel particulate filter was not allowed. Use the OEM service information to confirm that the OEM settings for the aftertreatment permit switch are configured correctly.
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 temperature for the exhaust gases 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.

Possible repairs:

1)Remove and clean the aftertreatment diesel particulate filter differential pressure sensor supply tubes.
2)If no short circuit is found, replace the aftertreatment diesel particulate filter differential pressure sensor.
3)Calibrate the ECM with the calibration containing corrections to resolve Fault Code 1981 and/or 1922.
4)Replace the six injectors.
5)Change the duty cycle of the application in order to increase the temperature of the exhaust gases entering the aftertreatment system.
6)If necessary, calibrate the ECM.