Case IH 214 – Engine Control Unit (ECU / ECM): Oil Temperature Sensor Voltage is above normal range

The system logs this code when the voltage at the oil temperature signal pin (specifically pin 42 of the sensor harness connector) indicates that the engine oil temperature has exceeded the critical threshold of 123°C (255°F). This triggers a red engine warning lamp, progressive power de-rate, and potential engine shutdown.

• MX Magnum
• STX Steiger
• Steiger
• Quadtrac
• Rowtrac
• 350
• 400
• 450
• 500
• 550
• 600 Tier 4
• Magnum

1. 1

   Inspect the oil cooler fins to ensure they are completely free of debris, dirt, or chaff that could block airflow

2. 2

   Inspect the oil lines running to and from the oil cooler for any physical restrictions, kinks, or blockages

3. 3

   Verify the operation of the oil cooler bypass valve to ensure it is not stuck in a position that bypasses the cooling circuit

4. 4

   Check the sensor harness connector (specifically pin 42) for high voltage shorts, damaged wires, or corrosion that could cause a false high-voltage reading

1. 1

   Cool Down

   Turn off the engine and allow the machine to cool down to a safe working temperature.

2. 2

   Clean the Cooling Package

   Using compressed air or a pressure washer, thoroughly clean the exterior fins of the engine oil cooler to restore proper airflow.

3. 3

   Clear Restrictions

   If the oil lines to/from the cooler are pinched or internally degraded, replace the restricted lines.

4. 4

   Service the Bypass Valve

   Remove and inspect the oil cooler bypass valve. If it is sticking or failing to route oil through the cooler, clean or replace the valve assembly.

5. 5

   Test/Replace the Sensor

   Disconnect the oil temperature sensor and test the harness for a short to voltage. If the wiring is intact, replace the Engine Oil Temperature Sensor.

6. 6

   Clear Codes

   Reconnect the harness, clear the fault codes using a diagnostic tool, and run the engine under load to verify that the oil temperature remains within the normal range and the code does not return.