John Deere 110 – Engine Control Unit (ECU) / Steering Module (XMC): Engine Coolant Temperature Extremely High / Engine Coolant Temperature Data Valid But Above Normal Operating Range

The engine control system has detected that the engine coolant temperature has exceeded the most severe safety threshold (typically above 115°C / 240°F). When this occurs, the system will actively derate maximum engine power, disable power boost, or command an engine shut-off to protect the engine from catastrophic damage.

• 6110M
• 6120M
• 6130M
• 6145M
• 6155M
• 6175M
• 6195M
• 6110R
• 6120R
• 6130R
• 6145R
• 6155R
• 6175R
• 6195R
• 6215R
• 6R Series (6110R to 6215R)
• 6J Series (6145J to 6205J)
• 7020 Series (7220 to 7520)
• 8R Series (8245R to 8400R)
• 9R/9000 Series 4WD
• CTS Series
• STS Series
• WTS Series
• 9540
• 9560
• 9640
• 9660
• 9680
• 9760
• 200CLC
• 319D
• 326D
• 329D
• 333E

1. 1

   Stop the machine, reduce the engine load immediately, and shut down the engine if the temperature does not drop

2. 2

   Check the radiator and cooler stack for external blockages caused by dirt, debris, or chaff (most common cause)

3. 3

   Check the engine coolant level in the radiator and overflow tank

4. 4

   Inspect coolant lines and hoses for pinches, leaks, or loose clamps

5. 5

   Check the water pump weep hole for signs of leaking

6. 6

   Verify the fan drive/viscous clutch is engaging properly (if the fan freewheels at all speeds when hot, the clutch has failed)

7. 7

   Check the thermostat (if the upper radiator hose is cool while the dashboard gauge shows hot, the thermostat is likely stuck closed)

8. 8

   Use an infrared temperature gun to measure the actual temperature of the engine block/thermostat housing and compare it to the monitor (if physically cool but code is active, the sensor or wiring is faulty)

1. 1

   Debris Removal

   Clean the entire cooler stack and radiator fins blowing from the engine side outward.

2. 2

   Resolve Leaks

   Replace any leaking hoses or a failed water pump, and refill the system with the specified John Deere coolant.

3. 3

   Thermostat Replacement

   If stuck closed, remove the thermostat housing, replace the thermostat, install a new gasket, and reassemble.

4. 4

   Sensor Removal

   Locate the Engine Coolant Temperature Sensor, disconnect the wiring harness connector (splice in a new pigtail connector if corroded or damaged), and remove the old sensor.

5. 5

   Sensor Installation

   Coat the new sensor's O-ring or threads with high-temperature grease/sealant as specified by the manual. Install the new sensor, tighten to OEM specifications, and reconnect the wiring harness.

6. 6

   Finalize

   Clear the diagnostic trouble codes from the ECU and XMC, then run the machine under load to verify the repair.