Cummins ISB6.7 CM2350 (2013-17) Fault Code: 221 PID: 108 SPN: 108 FMI: 3 Barometric Pressure Sensor Circuit- Voltage Above Normal or Shorted to High Source

Cummins ISB6.7 CM2350 (2013-17) Fault Code: 221 PID: 108 SPN: 108 FMI: 3 Barometric Pressure Sensor Circuit- Voltage Above Normal or Shorted to High Source

Circuit Description
The combination turbocharger compressor intake pressure/temperature sensor is used to measure ambient air pressure. The pressure measuring portion of the sensor responds to pressure changes in the atmospheric pressure, which occur based on elevation at which the engine is presently operating. The turbocharger compressor intake pressure sensor has a 5 volt supply circuit, a pressure sensor signal voltage, and a return circuit. The ECM will detect a low signal voltage when the vehicle is operating at high altitudes. The ECM will detect a high signal voltage when the vehicle is operating at sea level altitudes.

Component Location
The combination turbocharger compressor intake pressure/temperature sensor is located in the original equipment manufacturer (OEM) intake air plumbing.

Conditions for Running the Diagnostics
This diagnostic runs continuously when the keyswitch is in the ON position or when the engine is running.

Conditions for Setting the Fault Codes
The Engine Control Module (ECM) detected the turbocharger compressor intake pressure sensor reading was out of range high.

Action Taken When the Fault Code is Active
1)The ECM illuminates the amber CHECK ENGINE lamp and/or the Malfunction Indicator Lamp (MIL) immediately when the diagnostic runs and fails.
2)A default value for the barometric pressure reading is used.
3)Exhaust Gas Recirculation (EGR) valve operation will be disabled.
4)Diesel exhaust fluid injection into the aftertreatment system is disabled.
5)Engine torque will be reduced if the engine is operated for an extended period of time with this fault active.

Conditions for Clearing the Fault Code
1)To validate the repair, perform a key cycle, start the engine and let it idle for 1 minute.
2)The ECM will turn off the amber CHECK ENGINE lamp immediately after the diagnostic runs and passes.
3)For On-Board Diagnostics (OBD) engines, the ECM will extinguish the Malfunction Indicator Lamp (MIL) after three consecutive trips where the diagnostic runs and passes.
4)The Reset All Faults command in INSITE? electronic service tool can be used to clear active and inactive faults, as well as extinguish the MIL for OBD applications.

Possible causes:
1) A short circuit to battery in the engine harness.
2) An open return circuit in the engine harness
3) A malfunctioning turbocharger compressor intake pressure/temperature sensor
4) A malfunctioning engine control module (ECM)