Aftertreatment 1 DPF differential Presure – Data Erratic, Intermittent, or Incorrect
Overview
CODE | REASON | EFFECT |
Fault Code: 1883 PID: S324 SPN: 3251 FMI: 2/2 LAMP: Amber SRT: |
The aftertreatment diesel particulate filter differential pressure sensor is reading an erratic value.
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Possible reduced engine performance.
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Aftertreatment Diesel Particulate Filter Differential Pressure Sensor Circuit
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Circuit Description
The engine control module (ECM) provides a 5 volt supply to the aftertreatment diesel particulate filter differential pressure sensor on the sensor supply circuit. The ECM also provides a ground on the sensor return circuit. The aftertreatment diesel particulate filter differential pressure sensor provides a signal to the ECM on the aftertreatment diesel particulate filter differential pressure sensor signal circuit. This sensor signal voltage changes, based on the differential pressure across the aftertreatment diesel particulate filter.
Component Location
The aftertreatment diesel particulate filter differential pressure sensor is mounted on the diesel particulate filter. It is a combination sensor that detects both diesel particulate filter differential pressure and outlet pressure. Refer to the original equipment manufacturer (OEM) service manual.
Conditions for Running the Diagnostics
This diagnostic consists of two parts:
One part runs when the keyswitch is initially turned ON before the engine is started
The second part runs continuously while the engine is running.
Conditions for Setting the Fault Codes
The Engine Control Module (ECM) detected the aftertreatment diesel particulate filter differential pressure was greater than 1.5 kpa [0.44 in HG] at initial key ON, or is not changing with engine conditions.
Action Taken When the Fault Code is Active
- The ECM illuminates the amber CHECK ENGINE lamp and/or malfunction indicator lamp (MIL) after the diagnostic fails on two consecutive trips.
- A default value for the aftertreatment diesel particulate filter differential pressure is used.
- Diesel exhaust fluid injection into the aftertreatment system is disabled.
- Active and stationary regeneration of the diesel particulate filter will be disabled.
- Exhaust gas recirculation (EGR) valve operation will be disabled.
- Engine torque will be reduced if the engine is operated for an extended period of time with this fault active.
Conditions for Clearing the Fault Code
- To validate the repair using a Diagnostic Road Test, utilize a route that incorporates both stop and go city type driving and steady state highway type driving. It may be necessary to load the unit for certain diagnostics in the ECM to run.
- To validate the repair using a Chassis Dynamometer, utilize a routine that incorporates acceleration and motoring events, steady state highway type operation, and load. This will simulate normal driving and allow the diagnostics in the ECM to run.
- Turn the key switch OFF and allow the ECM to completely powerdown.
- To validate the repair, perform a key cycle and leave the key in the ON position for 2 minutes. Then start the engine and let it idle for 1 minute.
- The fault code status displayed by the recommended Cummins electronic service tool or equivalent will change to INACTIVE immediately after the diagnostic runs and passes.
- The ECM will turn off the amber CHECK ENGINE lamp immediately after the diagnostic runs and passes.
- For On-Board Diagnostics (OBD) engines, the ECM will extinguish the Malfunction Indicator Lamp (MIL) after three consecutive trips where the diagnostic runs and passes.
- The “Reset All Faults” command in the recommended Cummins electronic service tool or equivalent can be used to clear active and inactive faults, as well as extinguish the MIL for OBD applications.
Possible causes of this fault code include:
- Stuck in-range aftertreatment diesel particulate filter differential pressure sensor reading
- High resistance in the aftertreatment diesel particulate filter differential pressure sensor signal or return wires
- Disconnected or damaged aftertreatment diesel particulate filter differential pressure sensor tubes
- Plugged aftertreatment differential pressure sensor ports could cause this fault code if pressure is held in the port after the engine is turned off.
- Frozen, plugged, or restricted aftertreatment DPF differential pressure sensor tubes.
- Reference the appropriate OEM wiring diagram when troubleshooting circuits that utilize wiring supplied by the OEM.
Troubleshooting Summary
Verification
Conditions
- Turn keyswitch ON.
- Connect the recommended Cummins electronic service tool or equivalent.
Action
- Use the recommended Cummins electronic service tool or equivalent to read the fault codes.
Specification
Before troubleshooting this fault code, troubleshoot any fault code that is active or has more than one inactive count within the last 25 engine operating hours from the following list:
- Aftertreatment DPF: 1879, 1881
Linked Solutions
- None
Repair
- Perform a search on the appropriate fault codes.
Validation
- None
Verification
Conditions
- Turn keyswitch OFF.
Action
- Visually inspect the aftertreatment differential pressure tubes for proper installation.
- Inspect the aftertreatment DPF differential pressure sensor tubes for signs of damage, plugging, kinks, leakage or loose connections.
In extreme cold ambient temperatures it is important to check for a frozen, plugged, or restricted aftertreatment DPF differential pressure sensor tubes. Ice can form in the aftertreatment DPF differential pressure sensor tubes causing obstruction/sticking and may not be present at the time of troubleshooting.
Specification
- If damage, kinks or blockages are found, then proceed to the Repair section.
Linked Solutions
- None
Repair
- Repair or replace DPF differential pressure sensor tubes.
Validation
- Check ECM Calibration Revision History
- Use the recommended Cummins® electronic service tool or equivalent to find the current ECM code and revision number in the ECM.
- Compare the ECM code and revision number in the ECM to the calibration revisions listed in the ECM Calibration Revision History Database for applicable changes related to this fault code.
- Refer to ECM Calibration Revision History Database.
- Connect all components
- Connect the recommended Cummins electronic service tool or equivalent.
- Operate the engine within the “Conditions for Clearing the Fault Code” found in the Overview section of the troubleshooting procedure.
- Verify that the fault code is no longer active.
Verification
Conditions
- Turn keyswitch OFF.
- Disconnect the OEM wiring harness connector from the ECM.
- Disconnect the accelerator pedal or lever from the OEM wiring harness.
- Disconnect the remote accelerator pedal or lever from the OEM wiring harness.
- Disconnect the engine coolant level sensor from the OEM wiring harness.
- Disconnect the fan speed sensor from the OEM wiring harness.
- Disconnect the aftertreatment DPF differential pressure sensor from the OEM wiring harness.
Action
- Inspect the pins and connectors for damage.
- Measure the resistance between the aftertreatment DPF differential pressure sensor SIGNAL pin in the OEM wiring harness ECM connector and all other pins in the OEM wiring harness ECM connector.
- Measure the resistance between the aftertreatment DPF differential pressure sensor SUPPLY pin in the OEM wiring harness ECM connector and all other pins in the OEM wiring harness ECM connector.
- Refer to the circuit diagram or wiring diagram for connector pin identification.
Specification
- A malfunctioning OEM wiring harness has been detected if the resistance is less than the following specification: 100k Ω
Linked Solutions
- None
Repair
- Repair or replace the OEM wiring harness.
Validation
- Connect all components
- Connect the recommended Cummins electronic service tool or equivalent.
- Disable the fault code.
- Operate the engine within the “Conditions for Clearing the Fault Code” found in the Overview section of the troubleshooting procedure.
- Verify that the fault code is no longer active.
- Check ECM Calibration Revision History
- Use the recommended Cummins electronic service tool or equivalent to find the current ECM code and revision number in the ECM.
- Compare the ECM code and revision number in the ECM to the calibration revisions listed in the ECM Calibration Revision History Database for applicable changes related to this fault code.
- Refer to ECM Calibration Revision History Database.
Verification
Conditions
- Connect all components.
- Turn keyswitch ON.
- Connect the recommended Cummins electronic service tool or equivalent.
Action
- Use the recommended Cummins electronic service tool or equivalent to read the fault codes.
- Use the recommended Cummins electronic service tool or equivalent to find the current ECM code and revision number in the ECM.
- Compare the ECM code and revision number in the ECM to the calibration revision listed in the ECM calibration revision history for applicable changes.
Specification
- If a calibration update for this fault code is available, the ECM calibration revision must be that revision or higher.
Linked Solutions
- None
Repair
- Prior to downloading the ECM calibration, check to see that all job images and all other troubleshooting has been documented as downloading an ECM calibration will remove the fault codes on the ECM.
- Download the updated ECM calibration code.
Validation
- Connect all components
- Connect the recommended Cummins electronic service tool or equivalent.
- Disable the fault code.
- Operate the engine within the “Conditions for Clearing the Fault Code” found in the Overview section of the troubleshooting procedure.
- Verify that the fault code is no longer active.
- Check ECM Calibration Revision History
- Use the recommended Cummins electronic service tool or equivalent to find the current ECM code and revision number in the ECM.
- Compare the ECM code and revision number in the ECM to the calibration revisions listed in the ECM Calibration Revision History Database for applicable changes related to this fault code.
- Refer to ECM Calibration Revision History Database.
Verification
Conditions
- Turn keyswitch OFF.
Action
- Verify all preceding solution verifications for this fault code have been performed.
Specification
- If the fault code is still active after all preceding solution verifications have been performed, then a malfunctioning aftertreatment DPF differential pressure sensor has been detected.
Linked Solutions
- None
Repair
- Replace aftertreatment DPF differential pressure sensor.
- Clean the DPF differential pressure sensor tubes.
Validation
- Connect all components
- Connect the recommended Cummins electronic service tool or equivalent.
- Disable the fault code.
- Operate the engine within the “Conditions for Clearing the Fault Code” found in the Overview section of the troubleshooting procedure.
- Verify that the fault code is no longer active.
- Check ECM Calibration Revision History
- Use the recommended Cummins electronic service tool or equivalent to find the current ECM code and revision number in the ECM.
- Compare the ECM code and revision number in the ECM to the calibration revisions listed in the ECM Calibration Revision History Database for applicable changes related to this fault code.
- Refer to ECM Calibration Revision History Database.
If all steps have been completed and no root cause has been identified, then follow the technical escalation process.