Cummins ISM CM870 (2003-06) Fault Code: 144 PID: P110 SPN: 110 FMI: 3/3 Engine Coolant Temperature 1 Sensor Circuit – Voltage Above Normal or Shorted to High Source. High signal voltage or open circuit detected at engine coolant temperature circuit.

The engine coolant temperature sensor shares return wires in the engine harness with other sensors. An open return can cause multiple fault codes to be active.

Before troubleshooting Fault Code 144, check for multiple fault codes.

Possible causes:

1)Open return circuit in the harness, connectors, or sensor
2)Open signal circuit or shorted to a voltage source.

Possible repair:

1)Replace the engine coolant temperature sensor.
2)Replace the ECM
3)Repair or replace the engine harness.