Case IH 2319 (519178.03) - DEC – Engine Control Unit (ECU): Lube Oil Pressure Sensor - short to high voltage

The signal voltage from the Lube Oil Pressure Sensor is exceeding the maximum expected threshold ('shorted high' or 'voltage is too high'). This typically means the sensor's signal wire is shorted directly to a high-voltage source, or there is an open circuit on the sensor's ground wire causing the voltage to float high.

• MAXXUM T4E
• Magnum Series (MX255, MX285)
• TG Series Tractors

1. 1

   Inspect the lube oil pressure sensor wiring harness for visible wire breaks, chafing, or melted insulation that could cause a short circuit to a high voltage source.

2. 2

   Verify that the oil pressure sensor power supply voltage is correct and that the ground circuit is intact (an open ground can cause the signal to read as a high voltage).

3. 3

   Disconnect the sensor and check the pins for corrosion, moisture, or damage.

4. 4

   If the wiring harness tests normal (no shorts to battery power and good continuity to the ECU), test the sensor itself for an internal short.

1. 1

   Power Down

   Turn off the tractor and disconnect the battery to prevent electrical spikes during the repair.

2. 2

   Locate the Sensor

   Locate the lube oil pressure sensor on the engine block.

3. 3

   Disconnect the Harness

   Unplug the electrical connector from the sensor.

4. 4

   Remove the Sensor

   Using an appropriate wrench or socket, carefully unscrew the faulty lube oil pressure sensor from its port. Have a rag ready to catch any residual oil.

5. 5

   Install the New Sensor

   Install the replacement sensor along with a new O-ring seal to prevent leaks. Thread it in by hand to prevent cross-threading, then tighten to the OEM torque specification.

6. 6

   Reconnect and Test

   Plug the wiring harness back into the sensor. Reconnect the battery, start the engine, and verify that the fault code clears and the oil pressure reads normally on the instrument cluster.