Aftertreatment Fuel Shutoff Valve Circuit – Voltage Above Normal or Shorted to High Source
Overview
| CODE | REASON | EFFECT |
| Fault Code: 1923 PID: S334 SPN: 3482 FMI: 3/3 LAMP: Amber SRT: |
High signal voltage detected at the aftertreatment fuel shutoff valve circuit.
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Possible reduced engine performance.
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Aftertreatment Fuel Shutoff Valve Circuit
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Circuit Description
The aftertreatment fuel shutoff valve is used to disable the fuel supply to the aftertreatment system.
Component Location
The aftertreatment fuel injector is installed in the exhaust system in the turbocharger adapter pipe. The aftertreatment fuel pressure sensor and aftertreatment fuel shutoff valve are installed in the shutoff valve manifold. The aftertreatment purge air actuator is located above the shutoff valve manifold.
Conditions for Running the Diagnostics
This diagnostic runs when the aftertreatment fuel shutoff valve is commanded off.
Conditions for Setting the Fault Codes
The Engine Control Module (ECM) detected the aftertreatment fuel shutoff valve pulse width modulated (PWM) signal was at system voltage when the pulse width modulated (PWM) signal was commanded OFF.
Action Taken When the Fault Code is Active
- The ECM illuminates the amber CHECK ENGINE lamp and/or the malfunction indicator lamp (MIL) immediately when the diagnostic runs and fails.
Active regeneration of the aftertreatment diesel particulate filter will be disabled unitl the next key cycle.
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, start the engine and perform the recommended Cummins electronic service tool or equivalent Aftertreatment Diesel Particulate Filter Regeneration Test.
- 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:
Fuel shutoff valve signal wire shorted to a voltage source in the harness
A damaged aftertreatment fuel shutoff valve.
Troubleshooting Summary
Verification
Conditions
- Turn keyswitch OFF.
- Disconnect the engine wiring harness connector from the ECM.
- Disconnect the aftertreatment fuel shutoff valve from the engine wiring harness.
Action
- Inspect the pins and connectors for damage.
- Measure the resistance between the aftertreatment fuel shutoff valve SIGNAL pin at the aftertreatment fuel shutoff valve engine wiring harness connector and the aftertreatment fuel shutoff valve SIGNAL pin at the engine wiring harness ECM connector.
- Measure the resistance between the aftertreatment fuel shutoff valve RETURN pin at the aftertreatment fuel shutoff valve engine wiring harness connector and the aftertreatment fuel shutoff valve RETURN pin at the engine wiring harness ECM connector.
- Refer to the circuit diagram or wiring diagram for connector pin identification.
Specification
- A malfunctioning engine wiring harness has been detected if the resistance is greater than the following specification: 10 Ω
Linked Solutions
- None
Repair
- Repair or replace the engine 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
- Turn keyswitch OFF.
- Disconnect the engine wiring harness connector from the ECM.
- Disconnect the aftertreatment fuel shutoff valve from the engine wiring harness.
Action
- Inspect the pins and connectors for damage.
- Measure the resistance between the aftertreatment fuel shutoff valve SIGNAL pin at the aftertreatement fuel shutoff valve connector of the engine wiring harness and battery SUPPLY pins of the engine wiring harness ECM connector.
- Refer to the circuit diagram or wiring diagram for connector pin identification.
Specification
- A malfunctioning engine wiring harness has been detected if the resistance is less than the following specification: 100k Ω
Linked Solutions
- None
Repair
- Repair or replace the engine 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
- Turn keyswitch OFF.
- Disconnect the aftertreatment fuel shutoff valve from the engine wiring harness.
- Disconnect the engine wiring harness connector from the ECM.
Action
- Inspect the pins and connectors for damage.
- Measure the resistance between the aftertreatment fuel shutoff valve SIGNAL pin at the aftertreatement fuel shutoff valve connector of the engine wiring harness and battery SUPPLY pins of the engine wiring harness ECM connector.
- Refer to the circuit diagram or wiring diagram for connector pin identification.
Specification
- A malfunctioning engine wiring harness has been detected if the resistance is less than the following specification: 100k Ω
Linked Solutions
- None
Repair
- Repair or replace the engine 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
- 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.
- Verify all preceding solution verifications for this fault code have been performed.
Specification
- If the fault code is still active or inactive with more than one count within the last 25 engine hours and all the preceding solution verifications have been performed, then a malfunctioning fuel shutoff valve has been detected.
Linked Solutions
- None
Repair
- Replace aftertreatment fuel shutoff valve.
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.