Massey Ferguson 94.04 – Engine ECU: Fuel Filter Pressure Sensor Low Voltage

The Engine Control Unit (ECU) has detected that the voltage signal from the fuel filter pressure sensor has dropped below the normal operating range (typically below 0.4V or 0.1V, depending on the specific engine generation). This usually indicates an electrical issue such as a short to ground, an open circuit, a loss of sensor power supply, or a completely failed sensor.

• 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
• 5400 Series
• 6400 Series
• 7400 Series
• 8400 Series
• 8600 Series

1. 1

   Visual Inspection: Inspect the wiring harness leading to the fuel filter pressure sensor. Look for chafed wires, melted insulation, or a short to ground.

2. 2

   Connector Check: Disconnect the sensor and check the pins for corrosion, moisture, or pushed-back terminals.

3. 3

   Voltage Supply Test: Turn the key to the ON position (engine off). Use a multimeter to probe the sensor connector. Verify that the sensor is receiving the correct reference voltage (typically 5V) from the ECU and has a good ground.

4. 4

   Filter/Pump Check: While less likely to cause an FMI 4 electrical code, verify that the low-pressure fuel filters are not completely blocked and that the lift pump is operating, as a total lack of pressure combined with a skewed sensor can sometimes bottom out the voltage reading.

1. 1

   Disconnect Battery

   Turn off the machine and disconnect the negative battery terminal to prevent electrical spikes.

2. 2

   Repair Wiring

   If the diagnostic checks revealed a short to ground or a broken 5V reference wire, repair the wiring harness using appropriate weatherproof splices.

3. 3

   Replace the Sensor

   If the wiring and ECU voltage supply are intact, the sensor itself has failed internally. Locate the fuel filter pressure sensor (typically mounted on or near the main fuel filter housing). Clean the area around the sensor to prevent dirt from entering the fuel system. Unscrew the old sensor and catch any residual fuel with a rag. Install the new OEM sensor and tighten to the manufacturer's specified torque. Reconnect the electrical harness.

4. 4

   Prime the Fuel System

   Turn the key to the ON position to allow the electric lift pump to prime the system and purge air.

5. 5

   Clear Codes

   Reconnect the battery, start the engine, and use a diagnostic tool (such as the AGCO WinEEM3/EEM4 Service Tool) to clear the stored 000094.04 fault code. Verify the warning lamp turns off.