Massey Ferguson 94.31 – Engine Control Unit (ECU): Fuel Filter Pressure Sensor Signal Outside Normal Range

The fuel filter pressure sensor is sending a voltage signal that falls outside the pre-programmed, acceptable parameters. This typically indicates an electrical issue (such as a failing sensor, loose contact, or wiring harness damage) or a severe physical restriction in the fuel system (like a completely plugged fuel filter).

• 4710
• 7724S
• 5712SL
• Interim Tier 4 (2012-2015)
• 7722
• 7722S
• 7615
• 5613
• 5713SL
• 7720S
• 7716
• 7718
• T4
• 7715
• 5710SL
• 7726
• 7616
• 7618
• 5608
• 4708
• 7619
• 7626
• 7726S
• 7624
• 4707
• 4709
• 5711SL
• 7614
• 7718S
• 5610
• 7620
• 7719
• 7714
• 7716S
• T4 (2015-2021)
• 5612
• 7622
• 7720
• Tier 4 (2015-2021)
• 5611
• 7715S
• 5609
• 7724

1. 1

   Inspect the fuel filter for severe contamination or clogs that can cause abnormal pressure readings.

2. 2

   Check the wiring harness leading to the fuel filter pressure sensor for loose contacts, chafed wires, or moisture/corrosion inside the connector.

3. 3

   Test voltage at the ECU connection pins at the sensor harness. Unplug the sensor and verify a steady 5Vdc between the reference and ground pins.

1. 1

   Preparation

   Turn off the tractor, remove the key, and disconnect the battery to prevent electrical shorts during the repair.

2. 2

   Locate the Sensor

   Locate the fuel filter pressure sensor, which is threaded directly into the fuel filter housing assembly.

3. 3

   Remove the Faulty Sensor

   Depress the locking tab on the electrical pigtail and disconnect the harness from the sensor. Use a wrench to carefully unscrew the sensor from the housing. Have a rag ready to catch any residual diesel fuel that may leak out.

4. 4

   Install the New Sensor

   Thread the new OEM pressure sensor into the housing. Tighten it to the manufacturer's specified torque (do not overtighten, as the housing or sensor threads can be damaged).

5. 5

   Replace the Fuel Filter

   Because restricted fuel flow often damages these sensors or triggers the code, it is highly recommended to replace the fuel filter element(s) at the same time.

6. 6

   Bleed the Fuel System

   If air was introduced into the fuel lines during the sensor or filter replacement, prime and bleed the fuel system according to your specific engine's manual.

7. 7

   Clear Codes

   Reconnect the battery, start the engine, and use a diagnostic scan tool to clear the 000094.31 fault code from the ECU. Run the tractor at operating RPM to ensure the code does not return.