Massey Ferguson 110.03 – Engine Control Unit (ECU): Engine Coolant Temperature Signal Voltage High

The controller is receiving a voltage signal from the coolant temperature sensor that exceeds the normal operating threshold, indicating an open circuit usually caused by a disconnected sensor, a broken wire, or an internally failed sensor.

• 4710
• 7724S
• 5712SL
• Interim Tier 4 (2012-2015)
• 7722
• 7722S
• 7615
• 5613
• 5713SL
• 7720S
• 7716
• 7718
• T4
• 7715
• 5710SL
• 7726
• 7616
• 7618
• 5608
• 4708
• 7619
• 7626
• 7726S
• 7624
• 4707
• 4709
• 5711SL
• 7614
• 7718S
• 5610
• 7620
• 7719
• 7714
• 7716S
• T4 (2015-2021)
• 5612
• 7622
• 7720
• Tier 4 (2015-2021)
• 5611
• 7715S
• 5609
• 7724
• 4600 series
• 5700 series
• 6600 series
• 6700 series
• 7600 series
• 5400 series
• 6400 series
• 4200 series
• 4300 series
• 6100 series
• 6200 series

1. 1

   Visually inspect the electrical connector at the coolant temperature sensor for disconnected plugs, broken wires, pushed-out pins, or heavy corrosion.

2. 2

   Perform a wiring/ECU test by disconnecting the sensor, turning the ignition ON, and measuring the voltage across the harness connector pins (should be a 5V reference voltage).

3. 3

   Perform a bypass test by shorting the sensor signal wire to the ground wire on the harness side. If the temperature gauge deflects to 'Full/High' or logs a 000110.04 code, the wiring and ECU are functioning correctly.

4. 4

   Measure the resistance across the pins of the temperature sensor with a multimeter. If it reads 'OL' (Open Loop) or infinite resistance, the sensor has failed internally.

1. 1

   Preparation

   Ensure the tractor engine is completely cool to prevent burns and relieve cooling system pressure.

2. 2

   Drain Coolant

   Partially drain the engine coolant below the level of the sensor to prevent a spill, or have the new sensor ready to quickly swap and minimize fluid loss.

3. 3

   Remove the Sensor

   Disconnect the wiring harness from the coolant temperature sensor. Use a deep socket or wrench to unthread the faulty sensor from the engine block or thermostat housing.

4. 4

   Install the New Sensor

   Thread the new sensor into the housing. (If the sensor does not have pre-applied thread sealant, apply a small amount of liquid thread sealant or Teflon tape). Tighten to OEM specifications.

5. 5

   Reconnect

   Plug the electrical connector back into the sensor. Ensure it clicks and locks into place.

6. 6

   Refill and Test

   Top off the engine coolant reservoir. Turn the key ON, clear the inactive 000110.03 fault code from the ECU, and start the engine. Verify that the temperature gauge reads correctly as the engine warms up and check for coolant leaks.