Case IH 3147 – Engine Control Module (ECM) / EDC: Engine Oil Temperature Too High

The engine oil temperature sensor has detected that the oil temperature has exceeded the maximum safe operating threshold.

• Case IH Magnum Series 235 - 340 (Series 4)
• Case IH Steiger / STX Series 350 to 600 horsepower
• Case IH Farmall Series (e.g., 115U)

1. 1

   Verify actual temperature using a diagnostic scan tool and compare it against the oil pan/cooler using an infrared laser thermometer

2. 2

   Check engine oil and coolant levels to ensure they are correct and not degraded

3. 3

   Inspect the engine oil cooler and radiator fins for blockages such as dirt, chaff, or debris

4. 4

   Inspect the wiring harness and connector leading to the oil temperature sensor for chafed wires, broken connections, or corrosion

5. 5

   Test the sensor's resistance with a multimeter and compare it to OEM specifications for the ambient temperature

1. 1

   Address Mechanical Overheating

   If the engine is genuinely overheating the oil, clean the radiator and oil cooler thoroughly. If the oil cooler is internally clogged or failing, drain the fluids and replace the oil cooler assembly.

2. 2

   Replace the Sensor

   If the diagnostic checks prove the sensor is reading inaccurately, turn off the machine and disconnect the battery. Locate the engine oil temperature sensor, disconnect the electrical harness, place a catch pan underneath, unthread the old sensor, install the new OEM temperature sensor, and reconnect the electrical harness.

3. 3

   Repair Wiring

   If a short or open circuit was found in the harness, splice in a new connector pigtail or repair the damaged wire using heat-shrink connectors.

4. 4

   Clear Codes

   Reconnect the battery, turn the key on, and use a diagnostic scan tool to clear fault code 3147. Run the engine up to operating temperature to verify the code does not return.