Spn 4364 Fmi 31 Cummins (2024)

FAQs

What is the code FMI 31 on a Cummins SPN 4364? ›

This fault code indicates that the nox emissions are not being reduced enough by the SCR catalyst. There are many possible causes for this fault code including:Degraded DEF fluid. A faulty SCR catalyst.

In summary, SPN 4364 FMI 18 is an engine error code related to the aftertreatment system of a diesel engine. It can indicate a variety of issues, ranging from a faulty NOx sensor to a malfunctioning DEF system.

Description This code sets when the Aftertreatment Control Module (ACM) detects that the Selective Catalyst Reduction (SCR) NOx Conversion efficiency is low.

SPN 521049/FMI 31

Description This Code Sets When There is a Code Present for the Diesel Exhaust Fluid (DEF) Tank Level, DEF Dosing Unit, DEF Pump, NOx Sensors, Blocked DEF Line, DEF Quality, NOx Efficiency, Selective Catalyst Reduction (SCR) Harness and/or SCR Sensor.

The SPN 23 FMI 31 code indicates that the engine is not receiving the proper amount of fuel. This can be caused by a variety of issues, including a clogged fuel filter, a faulty fuel pump, or a problem with the fuel injectors.

SPN is short for suspect parameter number. It identifies which electrical circuit, part or component of your truck isn't working properly. FMI stands for failure mode identifier—this part of the fault code tells you what type of problem your truck has.

Using a code reader tool, connect to the ECM and find the “fault codes” tab. The displayed codes can generally be clicked on one by one. Another option is to select “erase all faults” and then follow the onscreen instructions. At the end of the procedure, the ignition key should be turned off.

This measurement happens between your inlet and outlet NOx sensors and it's called your SCR NOx efficiency. If the SCR NOx efficiency goes below 70%, then these fault codes get set “Active.” The only way you can clear these codes is by doing a forced regen with the SCR NOx efficiency above 70%.

Cummins ReCon® NOx sensors are the smart, low-cost replacement choice to help keep your engine's aftertreatment system operating normally. When a NOx sensor fails it can prompt multiple fault codes; capping the engine output, placing it in limp mode. 1.

SPN stands for Suspect Parameter Number. It's a diagnostic trouble code that provides detailed information about specific faults detected by the vehicle's ECU, making it easier to identify and address issues within the vehicle's electronic systems.

What is the NOx sensor behind the SCR catalyst? ›

NOx Sensor for NOx aftertreatment system

The sensor located upstream of the SCR catalyst directly measures the engine-out NOx gas concentration, which helps determine the optimum amount of urea injection. The NOx sensor downstream of the SCR catalyst is used to monitor the performance of the catalyst.

The P2200 diagnostic code indicates issues within a vehicle's NOx sensor circuit in engine bank 1. This is a potentially serious issue that requires attention to prevent dangerous situations from developing and secondary issues from forming within the vehicle.

Service Principal Name (SPN), used in the Kerberos protocol. Service provider name, stored on mobile phone subscriber identity module (SIM)

The FMI may indicate that a problem with an electronic circuit or an electronic component has been detected. The FMI may also indicate that an abnormal operating condition has been detected. The codes are displayed in the form “SPN – FMI”.

An aftertreatment system is a method or device for reducing harmful exhaust emissions from internal-combustion engines. In other words, it is a device that cleans exhaust gases to ensure the engines meet emission regulations.

4364 1 fault occurs when the outlet Nox is higher than expected. This is, be caused by either a faulty Nox sensor or poor quality DEF contaminating the system and potentially causing problems or failure with your scr and after treatment components.

Failure Mode Identifiers (FMI) are used to communicate what the ECU has detected, not the root cause of the problem. For example 100-03 “Engine Oil Pressure: Voltage above normal”. The system detected that the signal voltage from this sensor input went above the valid voltage range.