Massey Ferguson 100.04 – Engine Control Unit (ECU): Engine Oil Pressure Sensor Low Voltage

This code indicates that the voltage signal from the engine oil pressure sensor has dropped below the acceptable minimum threshold (typically falling below 0.099V). This condition usually points to a failed sensor, a wiring harness issue (such as an open circuit or a short to ground), or potentially a severe drop in actual engine oil pressure causing the sensor to bottom out.

• 5710SL
• 5711SL
• 5712SL
• 5713SL
• T4
• 4707
• 4708
• 4709
• 4710
• 5608
• 5609
• 5610
• 5611
• 5612
• 5613
• 7614
• 7615
• 7616
• 7618
• 7619
• 7620
• 7622
• 7624
• 7626
• 7714 through 7726S

1. 1

   Verify Oil Level: Manually check the engine oil level using the dipstick to ensure the engine is not starved of oil.

2. 2

   Verify Actual Oil Pressure: Connect a mechanical oil pressure gauge to the test port on the engine block. Start the engine and confirm that the engine is producing adequate mechanical oil pressure. If the mechanical pressure is normal, the issue is electrical.

3. 3

   Inspect Wiring and Connector: Locate the oil pressure sensor (typically located on the left side of the engine block toward the rear, utilizing a 3-pin plug). Inspect the connector and harness for corrosion, frayed wires, or signs of a short to ground.

1. 1

   Preparation

   Turn off the engine and allow it to cool. Relieve any residual system pressure.

2. 2

   Clean the Area

   Thoroughly clean the area around the sensor on the engine block to prevent dirt or debris from entering the oil gallery during removal.

3. 3

   Removal

   Disconnect the 3-pin electrical harness from the sensor. Use a wrench to carefully unscrew and remove the faulty oil pressure sensor.

4. 4

   Preparation of New Sensor

   Apply a proper thread sealant rated for oil/petroleum applications to the threads of the new sensor (if it does not come with pre-applied sealant).

5. 5

   Installation

   Thread the new sensor into the engine block and tighten it to the manufacturer's specifications. Do not overtighten, as this can crack the housing.

6. 6

   Reconnection

   Reconnect the electrical harness to the new sensor.

7. 7

   Testing

   Start the tractor and let it idle. Check the sensor fitting for any oil leaks. Increase the RPM and verify that there are no leaks under higher pressure. Ensure the 00100.04 fault code clears from the dashboard/ECU.