Case IH F-110-31 - ECU – Engine Control Unit (ECU): Engine Coolant Temperature - Condition Exists

The engine coolant temperature has exceeded the safe operating threshold (engine protection limit). To prevent catastrophic engine damage from overheating, the control module automatically enforces a torque limitation (engine derate). In some engine configurations, the system may also force the EGR valve closed.

• MAGNUM AFS Connect
• Magnum
• Steiger
• Farmall
• MXM series
• Axial-Flow 7120
• Axial-Flow 8120
• Axial-Flow 9010
• Axial-Flow 240 series
• Patriot 4440

1. 1

   Visually inspect the cooling package (radiator, charge air cooler, and grilles) for blockages caused by dirt, dust, or crop chaff (most common cause).

2. 2

   Verify the coolant level in the expansion tank and radiator (only when the engine is cold).

3. 3

   Inspect hoses, the water pump, and the radiator for visible coolant leaks.

4. 4

   Check the fan drive belt for proper tension and inspect the viscous fan clutch for proper engagement.

5. 5

   Test the Engine Coolant Temperature (ECT) sensor resistance with a multimeter (resistance should decrease as temperature increases). Check the 5V reference circuit and wiring harness for shorts or open circuits.

6. 6

   Ensure the engine thermostat is not stuck closed.

1. 1

   Safety First

   Park the machine on a level surface, turn off the engine, and allow it to cool completely. Never open a hot cooling system, as pressurized coolant can cause severe burns.

2. 2

   Clean the Cooling Package

   If debris is found during the diagnostic check, use compressed air or a pressure washer (at a safe distance to avoid bending fins) to blow out the radiator fins from the inside out.

3. 3

   Replace the ECT Sensor

   If diagnosed as faulty: Locate the coolant temperature sensor, disconnect the electrical connector, place a catch pan under the engine, unscrew the faulty sensor, install the new sensor and tighten to the manufacturer's specified torque, and reconnect the electrical harness.

4. 4

   Refill and Bleed

   Top off the engine coolant with the correct CNH specification coolant. Run the engine with the radiator cap off to bleed any trapped air from the system.

5. 5

   Clear Codes

   Use the Case IH Electronic Service Tool (EST) or an equivalent heavy-duty scan tool to clear the inactive fault codes and run the machine under load to verify the repair.