Massey Ferguson 000157.03 – ECU: Fuel Rail Pressure Sensor High Voltage

The Engine Control Unit (ECU) has detected an abnormally high voltage signal from the fuel rail pressure sensor. In a common rail fuel system, the ECU relies on this sensor to monitor and control the high pressure required for efficient fuel injection. A high voltage reading typically signifies a short circuit to a power source or an open circuit in the ground or signal return line, indicating a potential issue with the sensor itself, the wiring, or the electrical circuit.

• 4700 Series
• 4707
• 4708
• 4709
• 4710
• 5400 Series
• 5600 Series
• 5608
• 5609
• 5610
• 5611
• 5612
• 5613
• 5700SL Series
• 5710SL
• 5711SL
• 5712SL
• 5713SL
• 6400 Series
• 6600 Series
• 6612
• 6613
• 6614
• 6615
• 6616
• 7400 Series
• 7600 Series
• 7614
• 7615
• 7616
• 7618
• 7619
• 7620
• 7622
• 7624
• 7626
• 7700 Series
• 7714
• 7715
• 7715S
• 7716
• 7716S
• 7718
• 7718S
• 7719
• 7720
• 7720S
• 7722
• 7722S
• 7724
• 7724S
• 7726
• 7726S
• 8600 Series
• 8650
• 8660
• 8670
• 8680
• 8690
• 8700 Series
• 8730
• 8732
• 8735
• 8737
• Telehandlers
• Combine Harvesters

1. 1

   Visually inspect the fuel rail pressure sensor's electrical connector and wiring harness for frayed or pinched wires, corrosion, moisture, and ensure it is securely fastened.

2. 2

   Check the ground circuit for continuity to ground on the ground pin of the connector (an open ground circuit can cause the signal voltage to read high).

3. 3

   Verify the 5-volt reference voltage from the ECU to the sensor's power supply pin using a multimeter with the key on and the sensor unplugged.

4. 4

   Test the signal voltage by back-probing the signal wire with the sensor connected. With the key on and engine off, voltage should be around 0.5 volts. A reading close to 5 volts indicates an internal short in the sensor or a short in the wiring.

1. 1

   Safety First

   Ensure the engine is cool. Relieve the pressure in the fuel system according to the manufacturer's instructions. Disconnect the negative battery terminal to prevent electrical shorts.

2. 2

   Locate the Sensor

   The fuel rail pressure sensor is mounted on the high-pressure common rail of the engine.

3. 3

   Clean the Area

   Thoroughly clean the area around the sensor to prevent any dirt or debris from entering the fuel rail upon removal.

4. 4

   Disconnect and Remove

   Disconnect the electrical connector from the sensor. Place a rag beneath the sensor to catch any residual fuel. Using the appropriate size wrench, carefully unscrew and remove the old sensor from the fuel rail.

5. 5

   Install the New Sensor

   Lightly lubricate the threads of the new sensor with clean engine oil, if recommended by the manufacturer. Thread the new sensor into the fuel rail by hand to avoid cross-threading. Torque the new sensor to the manufacturer's specified value. Do not overtighten.

6. 6

   Final Steps

   Reconnect the electrical connector securely. Reconnect the negative battery terminal. Prime the fuel system if necessary. Start the engine and check for any fuel leaks around the new sensor. Clear the fault codes using a diagnostic tool and verify that the 000157.03 code does not reappear.