Aftertreatment Fuel Shutoff Valve 1 Circuit – Voltage Above Normal, or Shorted to High Source
|Fault Code: 1923
Aftertreatment Fuel Shutoff Valve 1 Circuit – Voltage Above Normal, or Shorted to High Source. High signal voltage detected at the aftertreatment fuel shutoff valve circuit.
Active aftertreatment diesel particulate filter regeneration will be disabled.
ISX – Aftertreatment Fuel Shutoff Valve 1 Circuit
ISM – Aftertreatment Fuel Shutoff Valve 1 Circuit
The aftertreatment fuel shutoff valve is used to disable the fuel supply to the aftertreatment system.
The aftertreatment fuel shutoff valve sensor is located in the aftertreatment shutoff valve assembly. Refer to Procedure 100-002 (Engine Diagrams) in Section E for a detailed component location view.
Conditions for Running the Diagnostics
This diagnostic runs within the first 30 seconds of the engine starting and prior to active regeneration of the diesel particulate filter.
Conditions for Setting the Fault Codes
The engine fuel shutoff valve circuit pulse width modulated (PWM) signal is detected to be at system voltage when the PWM voltage is turned off.
Action Taken When the Fault Code is Active
- The electronic control module (ECM) illuminates the amber CHECK ENGINE light immediately when the diagnostic runs and fails.
- Active aftertreatment diesel particulate filter regeneration will be disabled.
Conditions for Clearing the Fault Code
The ECM will turn off the amber CHECK ENGINE light immediately after the diagnostic runs and passes.
The fault code will clear within 30 seconds of starting the engine or prior to an active regeneration event of the diesel particulate filter.
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. Refer to Procedure 019-032 (ECM Calibration Code) in Section 19 in the corresponding Troubleshooting and Repair Manual for the engine being serviced.
Possible causes of this fault code include:
- Open return circuit in the engine harness, connectors, or shutoff valve.
- Fuel shutoff valve signal wire shorted to a voltage source in the harness.
- A damaged aftertreatment fuel shutoff valve.