Cummins ISX CM870 (2003-06) Fault Code: 153 PID: P105 SPN: 105 FMI: 3/3 Intake Manifold 1 Temperature Sensor Circuit – Voltage Above Normal or Shorted to High Source. High signal voltage detected at intake manifold air temperature circuit.

The intake manifold air temperature sensor shares return wires in the engine harness with other sensors. Opens and shorts in the engine harness can cause multiple fault codes to be active. Check active fault codes with multiple counts first.

Possible causes:

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

Possible repair:

1)Replace the intake manifold air temperature sensor.
2)Replace the ECM.
3)Repair or replace the engine harness