John Deere 000110.16 – ECU: High Temperature Condition

The engine's coolant temperature has exceeded a preset limit (at or above 112°C), signaling a high-temperature condition. This fault will often trigger an audible alarm and may cause the engine to limit power (derate) to prevent damage.

• 8130
• 8230
• 8330
• 8430
• 8530
• 8120
• 8220
• 8320
• 8420
• 8520
• 5085E
• 5090E
• 5100E

1. 1

   Check coolant level in the reservoir and radiator (ensure engine is completely cool before checking) and top off if low

2. 2

   Inspect the radiator, oil cooler, and cooling package for dirt, chaff, or debris obstructing airflow

3. 3

   Visually inspect all coolant hoses, the radiator, and the water pump for any signs of leaks

4. 4

   Ensure the cooling fan is functioning correctly and that the fan belt is intact and has proper tension

1. 1

   Identify the Coolant Temperature Sensor

   The sensor is typically located on the engine block, often near the thermostat housing.

2. 2

   Test the Sensor

   Disconnect the sensor's electrical connector. Using a multimeter set to measure resistance (Ohms), measure across the sensor's terminals. A reading can be taken with the engine cold and then again when warm to see if the resistance changes. A sensor that shows an open circuit or no change in resistance is likely faulty. For a more precise test, remove the sensor and submerge it in water of a known temperature (e.g., cold and then hot water) while measuring the resistance to check against specifications if they can be found in a technical manual.

3. 3

   Inspect Wiring

   Check the wiring harness and connector leading to the ECT sensor for any signs of damage, corrosion, or loose connections. Repair as necessary.

4. 4

   Check Thermostat

   A thermostat stuck in the closed position will prevent coolant from circulating to the radiator, causing the engine to overheat. If the engine overheats but the radiator remains cool, a faulty thermostat is a likely cause.

5. 5

   Replace Faulty Components

   If the ECT sensor is determined to be faulty, replace it with a new OEM part. If the thermostat is diagnosed as the issue, it should also be replaced. After replacement, ensure the cooling system is properly filled and bled of any air.