Massey Ferguson E157.04 – Engine Control Unit (ECU): Fuel Rail Pressure Sensor Low Voltage

The controller is seeing a signal voltage from the fuel rail pressure sensor that has dropped below the normal operating threshold. This is almost always caused by a short to ground in the wiring, an open circuit, or an internal failure of the sensor itself.

• 7616
• 5612
• 7622
• Interim Tier 4 (2012-2015)
• 7614
• 5611
• 7615
• 5610
• 5613
• 7620
• 5609
• 7618
• 5608
• 7619
• 7626
• 7624
• 4607M
• 4608
• 4609
• 4610
• 4707
• 4708
• 4709
• 4710
• 5465
• 5470
• 5710SL
• 5711SL
• 5712SL
• 5713SL
• 6465
• 6475
• 6480
• 6497
• 6499
• 6612
• 6613
• 6614
• 6713
• 7465
• 7497
• 7617
• 7621
• 7623
• 7625
• 7714
• 7715
• 7716
• 7717
• 7718
• 7719
• 7720
• 7721
• 7722
• 7723
• 7724
• 7725
• 7726
• 8450
• 8480
• 8650
• 8680
• 8727
• 8728
• 8729
• 8730
• 8731
• 8732
• 8733
• 8734
• 8735
• 8736
• 8737
• 8738
• 8739
• 8740
• 2604H
• 2605H
• 2606H
• 2607H

1. 1

   Inspect the wiring harness leading to the fuel rail pressure sensor for chafing, melting, or a short to ground against the engine block.

2. 2

   Disconnect the 3-pin connector at the sensor and look for moisture, corrosion, or pushed-out pins.

3. 3

   With the key ON and engine OFF, use a multimeter to check the harness side of the connector for a 5V reference signal and a good ground.

4. 4

   If the 5V reference and ground are present and the signal wire has continuity back to the ECU without shorting to ground, verify if the sensor has failed internally.

1. 1

   Depressurize and Prep

   Turn off the tractor and disconnect the negative battery cable. Wait at least 5–10 minutes for the high-pressure common rail to naturally depressurize.

2. 2

   Locate the Sensor

   Find the fuel rail pressure sensor, which is threaded directly into the high-pressure common fuel rail on the engine.

3. 3

   Clean the Area

   Thoroughly clean the area around the sensor with brake cleaner and compressed air to ensure no dirt or debris falls into the fuel rail when the sensor is removed.

4. 4

   Remove the Sensor

   Unplug the 3-pin electrical connector. Use a deep socket or wrench to carefully unthread the old sensor.

5. 5

   Install the New Sensor

   Thread the new sensor into the rail by hand to prevent cross-threading. Torque it to the manufacturer's exact specification (over-tightening can damage the rail; under-tightening will cause high-pressure fuel leaks).

6. 6

   Reassembly

   Reconnect the 3-pin electrical harness. Reconnect the battery.

7. 7

   Test

   Turn the key to the ON position (without starting) to let the lift pump prime the system. Check for leaks. Clear the E157.04 fault code using a diagnostic tool, then start the engine and verify the code does not return.