Cummins Fault Code 2347

24/10/2025

Overview

CODE

REASON

EFFECT

Fault Code: 2347
PID: P404
SPN: 2629
FMI: 0/15
LAMP: None
SRT:

High turbocharger compressor outlet air temperature has been calculated by the engine control module (ECM).

Possible reduced engine performance

Cummins Fault Code 2347 — Engine Control Module (ECM)

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 turbocharger compressor outlet temperature sensor in the system. The turbocharger compressor outlet air temperature is a calculation of temperature of the air after it is compressed by the turbocharger compressor, but before exhaust gas recirculation (EGR) is mixed into the system, and before it enters the charge-air cooler.

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 the turbocharger compressor outlet temperature was greater than 250Â°C [482Â°F].

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 calculated compressor outlet temperature.

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 the recommended Cummins electronic service tool or equivalent will change to INACTIVE immediately after the diagnostic runs and passes.
The “Reset All Faults” command in the recommended Cummins electronic service tool or equivalent can be used to clear active and inactive faults, as well as extinguish the MIL for OBD applications.

Shop Talk

Possible causes of this fault code include:

Air intake leaks allowing hot under-hood air to enter the intake system

Faulty intake manifold pressure readings

High turbocharger speed readings

Faulty barometric pressure readings

Stuck variable geometry turbocharger.

Note: Unless the issue is a malfunctioning 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 malfunction has been found and repaired.