New Holland ENG 212 – Engine Controller (ENG / ECU): Oil Temperature Sensor Voltage is too high.

The Engine Control Unit (ECU) is receiving a voltage signal from the engine oil temperature sensor that exceeds the maximum normal operating threshold. This almost always indicates an open circuit (such as a broken wire or unplugged connector) or a short to power (+V).

• T8000 series
• TG series
• Magnum series
• MX series

1. 1

   Locate the engine oil temperature sensor on the engine block and inspect the sensor's electrical connector for disconnected plugs, backed-out pins, corrosion, or water intrusion.

2. 2

   Trace the wiring harness from the sensor back to the Engine Controller, looking for chafed wires, melted insulation, or pinch points that could cause a short to a power source or an open circuit.

3. 3

   Disconnect the sensor and turn the key to the ON position to check the harness side for the proper 5V reference signal and a good ground.

4. 4

   Measure the resistance across the sensor's terminals with a multimeter; if the sensor reads 'OL' (open loop) or infinite resistance, it has failed internally and must be replaced.

1. 1

   Prep the Machine

   Park the machine on a level surface, turn off the engine, and disconnect the negative battery terminal to prevent electrical spikes.

2. 2

   Locate the Sensor

   Locate the faulty engine oil temperature sensor on the engine block or oil filter housing.

3. 3

   Remove the Sensor

   Disconnect the electrical harness plug. Place a catch pan underneath the sensor area, as a small amount of engine oil may leak out when the sensor is removed. Use a deep socket or wrench to unthread the sensor.

4. 4

   Install the New Sensor

   Inspect the threads of the new sensor. If it does not have pre-applied thread sealant, apply a small amount of liquid thread sealant (do not use Teflon tape, as it can break off into the oil system). Thread the new sensor in by hand, then tighten to the OEM torque specification.

5. 5

   Reassemble

   Reconnect the electrical harness plug, ensuring it clicks securely into place.

6. 6

   Test and Clear Codes

   Reconnect the battery. Turn the ignition key to the ON position and use the tractor's onboard diagnostic display or a CNH diagnostic tool to clear the inactive ENG 212 fault code. Start the engine, check for oil leaks around the new sensor, and verify that the code does not return.