Cummins X15 CM2350 X116B Performance Series (2018 & Newer) Fault Code: 4841 PID: SPN: 6653 FMI: 0/16 Engine Injector Metering Rail 1 Cold Start Pressure – Data Valid But Above Normal Operating Range – Moderately Severe Level

Lamp:
Amber

Reason:
High fuel rail pressure detected.

Effect:
Engine may run rough, may stop running, may not start, or may be difficult to start.

Circuit Description:
The Engine Control Module (ECM) provides a 5 volt supply to the fuel rail pressure sensor using a dedicated sensor supply circuit. The ECM also provides a ground on the sensor return circuit. The fuel rail pressure sensor provides a primary fuel pressure signal to the ECM on the fuel rail pressure sensor signal 1 circuit. The sensor also provides a secondary fuel pressure sensor signal on the fuel rail pressure signal 2 circuit. This sensor signal voltage changes based on the pressure in the fuel rail. The ECM will detect a high signal voltage at high rail pressure conditions. The ECM will detect a low signal voltage during low rail pressure conditions.

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 only runs when the coolant temperature and intake air temperature are below calibrated values.

Conditions for Setting the Fault Code:
The Engine Control Module (ECM) detected the fuel rail pressure reading was greater than the commanded fuel rail pressure.

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.

Conditions for Clearing the Fault Code:
1. The engine coolant temperature must be below 76°C [168°F] and the intake air temperature must be below 20°C [68°F].
2. Start and idle the engine for 1 minute.
3. The fault code status displayed by the recommended diagnostic tool or equivalent will change to inactive immediately after the diagnostic runs and passes.
4. The ECM will turn off the amber check engine lamp immediately after the diagnostic runs and passes.
5. 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.
5. The “reset all faults” command in the recommended diagnostic tool or equivalent can be used to clear active and inactive faults, as well as extinguish the MIL for OBD applications.

Shop Talk:
A fuel pump actuator with excessive leakage or a damaged inboard O-ring will result in high fuel rail pressures at idle or light load.