John Deere 100.03 – ECU: Engine Oil Pressure Sensor Signal Is High

The controller is detecting that the voltage signal from the engine oil pressure sensor is exceeding the specified high-voltage threshold. This condition typically indicates an electrical issue rather than an actual mechanical oil pressure failure, such as a short to a power source (12 volts), an open ground in the sensor circuit, or a complete internal failure of the sensor itself.

• 5085E
• 5090E
• 5090EL
• 5100E
• 5085M
• 5100M
• 5100MH
• 5100ML
• 5115ML
• 5090M
• 5115M
• 6110M
• 6120M
• 6130M
• 6145M
• 6155M
• 6175M
• 6195M
• 6110R
• 6120R
• 6130R
• 6145R
• 6155R
• 6175R
• 6195R
• 6215R
• 7R
• 8R
• 9R
• 444J
• 544J
• 624J
• 744K
• 824K
• 844K
• 850J
• 135D
• 210G
• 250GLC
• 350GLC
• 450DLC
• 319D
• 323D

1. 1

   Check engine oil level on the dipstick to rule out catastrophic fluid loss.

2. 2

   Inspect the wiring harness from the Engine Oil Pressure Sensor back to the ECU. Look for rubbed-through insulation, pinched wires, or areas where the signal wire might be shorting to a 12V power source.

3. 3

   Check for an open ground in the sensor circuit. Test the ground pin at the sensor connector for continuity to the chassis/ECU ground.

4. 4

   Inspect the sensor connector for water intrusion, corrosion, or bent pins.

5. 5

   Clear the code via the service monitor and retest. If the code immediately returns upon key-on (even at zero engine speed), the sensor has likely failed internally.

1. 1

   Power Down

   Turn off the machine, remove the key, and disconnect the negative battery cable to prevent electrical spikes.

2. 2

   Locate the Sensor

   Locate the Engine Oil Pressure Sensor on the engine block (usually near the oil filter housing or main oil gallery).

3. 3

   Disconnect

   Unplug the 3-pin electrical connector from the sensor.

4. 4

   Remove Sensor

   Using an appropriately sized deep socket or wrench, unthread the faulty oil pressure sensor from the engine block. Have a rag ready, as a small amount of oil may weep out.

5. 5

   Install New Sensor

   Thread the new OEM sensor into the port. (Note: Many John Deere sensors come with pre-applied thread sealant; if not, apply a sensor-safe thread sealant). Tighten to the manufacturer's torque specification.

6. 6

   Reconnect

   Plug the electrical harness back into the sensor, ensuring the locking tab clicks into place.

7. 7

   Test

   Reconnect the battery, turn the key on, and enter the diagnostic monitor to clear the stored 000100.03 code. Start the engine and verify that the code does not return and that the oil pressure reads normally on the dash.