Massey Ferguson 100.03 – ECU: Engine Oil Pressure Sensor High Voltage

The engine control module is receiving a voltage signal from the oil pressure sensor that exceeds the normal operating threshold (typically exceeding 4.85V). This condition almost always points to an electrical issue: an open circuit, a short to power in the sensor wiring, or an internally shorted/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

1. 1

   Check Oil Levels: Verify the engine oil level on the dipstick as a baseline precaution.

2. 2

   Visual Inspection: Inspect the wiring harness leading to the engine oil pressure sensor for chafing, melted insulation, or pinched wires that could cause a short to power.

3. 3

   Connector Check: Disconnect the sensor plug and check for corrosion, water ingress, or backed-out pins.

4. 4

   Voltage Test: With the key ON and engine OFF, probe the sensor signal wire. If voltage is >4.85V while disconnected, there is a short to power in the harness. If voltage is normal but jumps high when plugged in, the sensor has failed internally.

1. 1

   Preparation

   Turn off the tractor, remove the key, and allow the engine to cool.

2. 2

   Clean the Area

   Thoroughly clean the area around the oil pressure sensor on the engine block to prevent dirt or debris from falling into the oil gallery when the sensor is removed.

3. 3

   Removal

   Disconnect the electrical connector. Use a properly sized deep socket or wrench to carefully unthread the old sensor from the block. Have a rag ready to catch any residual oil drips.

4. 4

   Installation

   Apply a small dab of thread sealant to the threads of the new sensor (if it does not come with pre-applied sealant). Thread the new sensor into the block by hand to prevent cross-threading.

5. 5

   Torque

   Tighten the sensor with a wrench. Do not overtighten, as these sensors have hollow brass or aluminum threads that can snap easily.

6. 6

   Reconnection

   Plug the electrical connector back in, ensuring it clicks securely into place.

7. 7

   Verification

   Start the engine and check for oil leaks around the new sensor. Use a diagnostic tool to clear the 000100.03 fault code from the ECU and verify that it does not return.