Cummins ISB4.5 CM2150 Fault Code: 3557 PID: SPN: 3360 FMI: 2 Aftertreatment Diesel Exhaust Fluid Controller – Data Erratic, Intermittent, or Incorrect.

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 electronic control module (ECM) via the J1939 data link connection.

Component Location
The location of the aftertreatment diesel exhaust fluid controller varies by application and original equipment manufacturer (OEM). The controller will typically be mounted to the vehicle frame or suitable rigid bracket using 3 or 4 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.

Conditions for Setting the Fault Codes
A reading that is too high or too low for the operating conditions has been detected on the sensor supply circuit between the diesel exhaust fluid controller and the dosing unit.

Action Taken When the Fault Code is Active
-The ECM illuminates the amber CHECK ENGINE lamp and/or the malfunction indicator lamp (MIL) immediately when the diagnostic runs and fails.
-Diesel exhaust fluid injection into the aftertreatment system is disabled.

Conditions for Clearing the Fault Code
-This fault code cannot be cleared with INSITE™ electronic service tool.
-To validate the repair, start the engine and let it idle for 1 minute.
-The ECM will turn off the amber CHECK ENGINE lamp and/or MIL immediately after the diagnostic runs and passes.
Use INSITE™ electronic service tool to verify that the fault code is inactive.
-The inactive fault code will be cleared from memory after 9600 hours of engine operation without a re-occurrence.

Shop Talk
The aftertreatment diesel exhaust fluid controller is not serviceable, and must be replaced upon determination of a component malfunction.