Circuit DescriptionThe 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 LocationThere 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 DiagnosticsThis diagnostic runs continuously when the engine is running.

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

Action Taken When the Fault Code is ActiveThe ECM logs the fault code immediately when the diagnostic runs and fails.Fuel is limited in an attempt to decrease the temperature of the exhaust gas entering the turbocharger.Conditions for Clearing the Fault CodeTo validate the repair, perform a key cycle, start the engine and let it idle for 1 minute.The ECM will turn off the amber CHECK ENGINE lamp 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 TalkThis fault code is an information fault code, indicating that the engine has been derated for high turbine intake temperature (exhaust temperature). No troubleshooting is necessary for this fault code. It is only an indicator that the engine power was derated to limit the exhaust temperature.

If the condition continues to exist, Fault Code 2451 will become active.

Possible Cause:1) ECM calibration