Cummins X12 CM2350 X119B (2018 & Newer) Fault Code: 3741 PID: SPN: 5571 FMI: 0 High Pressure Common Rail Fuel Pressure Relief valve- Data Valid But Above Normal Operational Range- Most Severe Level

Circuit Description
The high-pressure relief valve is a mechanical device that opens when the fuel pressure in the fuel rail exceeds a critical warning limit.

Component Location
The high-pressure fuel pump is mounted to the gear housing. The fuel pump actuator is mounted on the fuel pump. The fuel pressure sensor is mounted in the high pressure fuel rail. The fuel pressure relief valve is mounted on the high pressure fuel rail.

Conditions for Running the Diagnostics
This diagnostic runs continuously when the engine is running.

Conditions for Setting the Fault Codes
The Engine Control Module (ECM) detected the fuel rail pressure had exceeded the fuel pressure relief valve limiting pressure, and the fuel pressure relief valve opened.

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.

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, perform a key cycle, start the engine and run it at high idle for 5 minutes.

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 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 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:

High fuel drain line restriction
A leaking or sticky fuel pump actuator
Air in the fuel
A plugged fuel pump actuator mounting adapter
This fault indicates that the fuel rail pressure was high enough to open the fuel rail pressure relief valve.

Possible Cause:
1) Rail Fuel pressure sensor failure
2) Suction side fuel filters failure
3) Fuel heaters valves are
4) OEM fuel lines
5) Fuel Tank Standpipes
6) Fuel FIlter failure
7) Fuel pump actuator failure
8) ECM calibration