Cummins ISX12 CM2250 (2010-12) Fault Code: 1974 PID: 101 SPN: 101 FMI: 16 Crankcase Pressure- Data Valid But Above Normal Operating Range-Least Severe Level

Circuit Description
The crankcase pressure sensor is used to monitor the pressure inside the crankcase. The engine control module (ECM) supplies the crankcase pressure sensor a 5 volt reference voltage. When the crankcase pressure is low, the sensor signal voltage is low. When the crankcase pressure is high, the sensor signal voltage is near the 5 volt reference voltage. The ECM monitors the crankcase pressure signal circuit voltage to calculate the pressure of the air within the crankcase.

Component Location
The crankcase pressure sensor is located near the crankcase ventilation element.

Conditions for Running the Diagnostics
This diagnostic runs continuously when the engine is running.

Conditions for Setting the Fault Codes
The ECM detected the crankcase pressure in the breather tube was greater than a calibrated value.

Action Taken When the Fault Code is Active
The ECM logs the fault code immediately when the diagnostic runs and fails.
Conditions for Clearing the Fault Code
To validate the repair, perform a key cycle, start the engine, and let it idle for 1 minute.
Use INSITE? electronic service tool ?Data Monitor/Logger? feature to monitor “Crankcase Pressure” with the engine running at idle. If the crankcase pressure reading is below 7.0 in H20, the repair has been validated.
The Reset All Faults command in INSITE? electronic service tool can be used to clear active and inactive faults, as well as extinguish the malfunction indicator lamp for on-board diagnostics applications.
The ECM will turn off the amber CHECK ENGINE lamp immediately after the diagnostic runs and passes.
The fault code status displayed by INSITE? electronic service tool will change to INACTIVE immediately after the diagnostic runs and passes.

Shop Talk
If this fault code is active, the crankcase breather system may need to be inspected.

Possible Cause:
1) N/A