Cummins ISX12 CM2250 (2010-12) Fault Code: 1927 PID: SPN: 3480 FMI: 3 Aftertreatment Fuel Pressure Sensor Circuit- Voltage Above Normal or Shorted to High Source

Circuit Description
The aftertreatment fuel pressure sensor is used to monitor the fuel pressure into the aftertreatment system. The electronic control module (ECM) supplies the aftertreatment fuel pressure sensor a 5 volt reference voltage. When the fuel pressure is low, the sensor signal voltage is low. When the fuel pressure is high, the sensor signal voltage is near the 5 volt reference voltage. The ECM monitors the aftertreatment fuel pressure signal circuit voltage to calculate the pressure of the fuel within the aftertreatment system.

Component Location
The aftertreatment fuel pressure sensor is located in the aftertreatment shutoff valve assembly.

Conditions for Running the Diagnostics
This diagnostic runs continuously when the keyswitch is in the ON position.

Conditions for Setting the Fault Codes
The ECM detects that the aftertreatment fuel pressure signal voltage is more than 4.8-VDC for more than 1 second.

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 until 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 let it idle for 1 minute.
The fault code status displayed by INSITE? electronic service tool will change to INACTIVE immediately after the diagnostic runs and passes.
The ECM will turn off the amber CHECK ENGINE lamp after the diagnostic runs and passes.
For On-Board Diagnostic (OBD) engines, the ECM will turn off the MIL after three consecutive trips where the diagnostic runs and passes.
The Reset All Faults command in INSITE? electronic service tool can be used to clear active and inactive faults, as well as extinguish the MIL for OBD applications

Shop Talk
Possible causes of this fault code include:

Open return circuit in the engine harness, connector, sensor
Signal wire shorted to sensor supply or battery voltage
A shorted sensor.

Possible Cause:
1) ECM failure
2) Engine Harness failure
3) ECM calibration