Cummins X12 CM2350 X119B (2018 & Newer) Fault Code: 2451 PID: SID 384 SPN: 2789 FMI: 16 Turbocharger Turbine Intake Temperature- Data Valid But Above Normal Operating Range- Moderately Severe Level

Circuit Description
The exhaust gas temperature is calculated by the engine control module (ECM). The exhaust gas temperature is derived by the ECM, based on engine operating conditions such as intake manifold air temperature, engine speed, injection timing, intake manifold pressure, and fuel flow.

Component Location
There is not a physical exhaust gas temperature sensor in the system. The exhaust gas temperature is a calculation of exhaust gas temperature before the turbocharger, and is also known as turbine intake temperature.

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

Conditions for Setting the Fault Codes
The Engine Control Module (ECM) calculated turbine inlet temperature was greater than a calibratible value.

Action Taken When the Fault Code is Active
The ECM logs the fault code immediately when the diagnostic runs and fails.
Fuel is limited in an attempt to decrease the exhaust gas temperature entering the turbocharger.
Conditions for Clearing the Fault Code
To validate the repair using a Diagnostic Road Test, utilize a route that incorporates both stop and go city type driving and steady state highway type driving. It may be necessary to load the unit for certain diagnostics in the ECM to run.
To validate the repair using a Chassis Dynamometer, utilize a routine that incorporates acceleration and motoring events, steady state highway type operation, and load. This will simulate normal driving and allow the diagnostics in the ECM to run.
The fault code status displayed by INSITE™ electronic service tool will change to INACTIVE immediately after the diagnostic runs and passes.
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.

Shop Talk
The most common cause of this fault code is low boost pressure. Low boost pressure can be caused by several factors: leaking charge-air cooler, damaged charge-air cooler piping or hose, loose charge-air cooler clamps, damaged intake manifold pressure sensor, damaged variable geometry turbocharger, damaged turbocharger control valve, or damaged turbocharger control shutoff valve.

This fault code can also be caused by a turbocharger fuel control derate, which can be viewed with INSITE™ electronic service tool, under the Engine Operating State. Turbocharger fuel control derates can be caused by several factors: high exhaust temperatures, turbocharger compressor inlet temperatures, and turbocharger compressor outlet temperatures.

Exhaust gas recirculation (EGR) system leaks can also cause this fault code. Inspect the EGR bellows and EGR connections for signs of leaks.

Note: This fault code will most likely not be active with no load in the shop. The engine must be loaded to trip this fault code, and to determine if the cause has been found and repaired. Running units on the dynamometer can sometimes cause this fault code to log, due to the stationary nature and high temperatures.

Possible Cause:
1) ECM calibration