ISX12/ISX11.9 CM2250 Fault Code: 4431 | SPN: 3360 | FMI: 13Aftertreatment Diesel Exhaust Fluid Controller – Out of Calibration

Overview

Circuit Description

The aftertreatment diesel exhaust fluid controller is the central control for the selective catalytic reduction (SCR) diesel exhaust fluid dosing system, and handles the dosing activity, tank level sensing, tank temperature sensing, line heating, and tank heating. The diesel exhaust fluid controller communicates to the engine control module (ECM) via the J1939 data link connection.

Component Location

The location of the aftertreatment diesel exhaust fluid controller varies by application and OEM. The controller will typically be mounted to the vehicle frame or suitable rigid bracket using three or four capscrews. Refer to the OEM service manual for a more detailed component location description.

Conditions for Running the Diagnostics

This diagnostic runs continuously when the keyswitch is in the ON position or when the engine is running.

Conditions for Setting the Fault Codes

The aftertreatment diesel exhaust fluid controller detected an internal error and communicated it to the Engine Control Module (ECM) via the SAE J1939 data link.

Action Taken When the Fault Code is Active

• The ECM illuminates the amber CHECK ENGINE lamp and/or malfunction indicator lamp (MIL) after the diagnostic fails on two consecutive trips.

Conditions for Clearing the Fault Code

• To validate the repair, perform a key cycle, start the engine and let it idle for 1 minute.
• 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 ECM will turn off the amber CHECK ENGINE lamp immediately after the diagnostic runs and passes.
• For On-Board Diagnostics (OBD) engines, the ECM will extinguish the Malfunction Indicator Lamp (MIL) after three consecutive trips where 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

The aftertreatment diesel exhaust fluid controller is not serviceable, and must be replaced when malfunctioning.

Reference the appropriate OEM wiring diagram when troubleshooting circuits that utilize wiring supplied by the OEM.

For intermittent power supply and datalink communication issues with aftertreatment components, it is highly recommended that the OEM Power Distribution Center fuses and relays be thoroughly checked for loose, missing, or intermittent connections.