Cummins ISB CM850 (2003-06) Fault Code: 2347 (ISC) PID: SPN: 2790 FMI: 15 Turbocharger Compressor Outlet Air Temperature (Calculated) – Data Valid but Above Normal Range – least severe level.

Possible causes:

1)Air intake leaks allowing hot underhood air to enter the intake system
2)Faulty intake manifold pressure readings
3)High turbocharger speed readings
4)Faulty barometric pressure readings
5)Stuck turbocharger control valve
6)Stuck variable geometry turbocharger.

NOTE: Unless the failure is a failed barometric pressure sensor or intake manifold pressure sensor, this fault code will most likely not be active with no load in the shop. The engine will most likely need to be loaded to trip this fault code, and to determine if the failure has been found and fixed.

Possible repairs:

1)Correct the cause of high intake air restriction. Check for plugged air filter or restricted air intake piping.
2)Repair the air intake piping.
3)Repair the charge-air cooler connections or charge-air cooler.
4)Replace the turbocharger.
5)Repair the air supply from the OEM air tanks.
6)Replace the turbocharger control valve.
7)Replace the turbocharger actuator.