Cummins ISB CM850 (2003-06) Fault Code: 124 PID: 102 SPN: FMI: 0 Intake Manifold 1 Pressure Sensor Circuit – Data Valid But Above Normal Operating Range – Moderately Severe Level.

Posted by PerDiezel Solutions on January 18, 2026

Cummins ISB CM850 (2003-06) Fault Code: 124 PID: 102 SPN: FMI: 0 Intake Manifold 1 Pressure Sensor Circuit – Data Valid But Above Normal Operating Range – Moderately Severe Level. Intake manifold pressure has exceeded the maximum limit for the given engine rating.

This fault code become active when the intake manifold pressure exceeds the maximum pressure limit for a given engine rating.

Possible causes:

1)Malfunctioning turbocharger wastegate
2)Wastegate tampering
3)Wrong turbocharger part
4)Possible tampering of the fuel system or turbocharger system.

The sensor return configuration for Euro 4 ISB engines has been changed for automotive wiring harnesses manufactured from February 2012 onward. The new style wiring harnesses can be be identified using the method below:

1)Disconnect the ECM connector
2)Disconnect the camshaft position sensor
3)Disconnect the intake manifold pressure/temperature sensor
4)Check for continuity between the intake manifold pressure/temperature sensor RETURN pin and the camshaft position sensor RETURN pin
5)Check for continuity between ECM pin 47 and the camshaft position sensor RETURN pin
6)Use the table below to determine which harness is fitted to the engine.

NOTE: QSB engines, all C series engines, and all L series engines are not affected by this change.

Possible repairs:

1)Replace the intake manifold pressure sensor

Cummins ISB CM850 (2003-06) Fault Code: 123 PID: 102 SPN: 102 FMI: 4 Intake Manifold Pressure Sensor Circuit – Voltage Below Normal or Shorted to Low Source. Low signal voltage detected at the intake manifold pressure circuit.

Cummins ISB CM850 (2003-06) Fault Code: 122 PID: 102 SPN: 102 FMI: 3 Intake Manifold Pressure Sensor Circuit – Voltage Above Normal or Shorted to High Source. High signal voltage detected at the intake manifold pressure circuit.

Cummins ISB CM850 (2003-06) Fault Code: 115 PID: 190 SPN: 612 FMI: 2 Engine Magnetic Crankshaft Speed/Position Lost Both of Two Signal – Data Erratic, Intermittent, or Incorrect. The ECM has detected that the primary engine speed sensor and the backup engine speed sensor signals are reversed.

Cummins ISB CM850 (2003-06) Fault Code: 111 PID: SID 254 SPN: 629 FMI: 12 Engine Control Module – critical internal failure. Error internal to the ECM related to memory hardware failures or internal ECM voltage supply circuits.

Cummins ISB CM850 (2003-06) Fault Code: FC0006 PID: SPN: FMI: Exhaust Gas Temperature Sensor Number 1 Circuit – Voltage Above Normal, or Shorted to High Source. High signal voltage or open circuit detected at the Exhaust Gas Temperature Sensor circuit.

Cummins ISB CM850 (2003-06) Fault Code: FC0005 PID: SPN: FMI: Exhaust Gas Temperature Sensor Number 1 Circuit – Voltage Below Normal, or Shorted to Low Source. Low signal voltage or open circuit detected at the Exhaust Gas Temperature Sensor circuit.

WARNING!