Cart $0.00
Subtotal: $0.00
No products in the cart.

Cummins ISX12 CM2250 (2010-12) Fault Code: 1911 (B) PID: 157 SPN: 157 FMI: 0 Injector Metering Rail 1 Pressure- Data Valid But Above Normal Operating Range- Most Severe Level

Circuit Description
The ECM monitors engine operating conditions, including the reading of rail fuel pressure, and changes the flow command to either increase (OPEN the fuel pump actuator) or decrease (CLOSE the fuel pump actuator) the fuel supply to the high-pressure pump.

Component Location
The fuel pump actuator is installed on the high-pressure fuel pump. The high-pressure relief valve is located on the fuel rail.

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

Conditions for Setting the Fault Codes
The ECM has verified that the fuel rail pressure has exceeded the fuel pressure relief valve limiting pressure, and the fuel pressure relief valve has opened.

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 and stationary regeneration of the diesel particulate filter will be disabled.
The exhaust gas recirculation (EGR) valve will be closed.
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 using a Diagnostic Road Test, utilize a route that incorporates both stop-and-go city driving and steady state highway driving. It may be necessary to load the unit for certain diagnostics in the ECM to run.
To validate the repair using a Chassis Dynamometer Test, utilize a routine that incorporates acceleration and motoring events, steady state highway operation, and load. This will simulate normal driving and allow the diagnostics in the ECM to run.
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
In normal engine operation, the ECM calibration varies the flow commanded to the fuel pump actuator to achieve the correct fuel rail pressure. System failures that cause loss of pressure control can cause the fuel rail pressure relief valve to open. The fuel rail pressure relief valve acts to protect the high-pressure components from over-pressurization. If the ECM detects that the fuel rail pressure relief valve is open without detection of a fuel pump actuator circuit error, Fault Code 1911 will become active. On certain applications, the ECM will attempt to reset automatically causing a momentary loss of power for less than 1 second.

Conditions that can cause Fault Code 1911:

Purging air through the fuel system can cause a pressure overshoot, therefore causing Fault Code 1911 to log. A few bubbles exiting the line during the air-in-fuel test is expected. A foamy appearance is an indication of a leak that allows air to enter, a severe inlet restriction that causes cavitation, or a system that is not yet primed. If fuel inlet restriction is not excessive (use Procedure 006-020 in the applicable service manual), the source of air entry can probably be isolated to one of the following: suction fuel lines, OEM fuel lines, suction-side fuel filter assemblies, or stand pipe(s) in the fuel tank(s).
Sustained periods of very low pressure under load, followed by pressure recovery overshoot. This can be caused by high restriction due to plugged filters (Fault Code 559 and 2372).
A tampered fuel pressure sensor that reads low, a biased pressure sensor, or a poor electrical connection.
If an intermittent electrical circuit problem with the fuel pump actuator circuit exists, it is possible for Fault Code 1911 to become active, then inactive during normal engine operation. ECM Fault Code 2311 is designed to detect electrical circuit issues with the actuator. Therefore, it is only necessary to inspect for damaged connectors or harness issues for Fault Code 1911 if no other fault codes exist. An electric fuel control actuator with excessive leakage will result in high rail fuel pressures at idle or light load.
Other conditions include ECM wiring harness issues, such as poor grounds, battery voltage spikes, electrical noise, low alternator output, and large disturbances of battery voltage, as when jump-starting the vehicle or the activation of a large grid heater load.
The fuel rail pressure sensor must also be checked. When checking the fuel rail pressure sensor accuracy, make sure the high-pressure fuel rail is not pressurized. The fuel pump, high-pressure fuel lines, and fuel rail contain very high-pressure fuel. Do not loosen any fittings while the engine is running. Wait at least 10 minutes after shutting down the engine before loosening any fittings in the high-pressure fuel system to allow pressure to decrease to a lower level. There can be a significant amount of time waiting for the rail to depressurize to zero on some engines. In such cases, it may be necessary to manually relieve the pressure from the high-pressure fuel rail.

Possible Cause:
1) Fuel Pressure sensor failure
2) Rail fuel pressure sensor failure
3) Fuel pressure relief valve failure
4) Suction side Fuel Filter failure
5) Fuel Filter failure
6) Fuel pump actuator failure
7) ECM calibration