Cummins ISX12 CM2250 (2010-12) Fault Code: 3755 PID: SPN: 5394 FMI: 2 Aftertreatment Diesel Exhaust Fluid Dosing Valve- Data Erratic, Intermittent, or Incorrect

Circuit Description
The electronic control module (ECM) monitors the NOx concentration in the engine’s exhaust gases using an aftertreatment intake NOx sensor and aftertreatment outlet NOx sensor. By comparing these two values, the ECM is able to determine the conversion efficiency of the SCR catalyst and dosing system.

Component Location
The primary components of the SCR exhaust aftertreatment system are the SCR catalyst, diesel exhaust fluid (DEF) dosing unit, DEF controller, DEF dosing valve, DEF tank, decomposition tube, various DEF lines, intake NOx sensor, and outlet NOx sensor. The locations of these components will vary depending on the vehicle application and the OEM.

Conditions for Running the Diagnostics
This diagnostic runs only during INSITE? electronic service tool Aftertreatment Diesel Particulate Filter Regeneration Test.

Conditions for Setting the Fault Codes
The ECM detects a malfunction in the diesel exhaust fluid dosing system resulting in lower than expected NOx conversion across the SCR catalyst.

Action Taken When the Fault Code is Active
The ECM will log the fault code immediately when the diagnostic runs and fails.

Conditions for Clearing the Fault Code
To validate the repair, perform INSITE? electronic service tool Aftertreatment Diesel Particulate Filter Regeneration Test.
The fault code status displayed by INSITE? electronic service tool will change to INACTIVE 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.

Shop Talk
This fault code is only used to assist in troubleshooting Fault Codes 3151, 3543 and/or 3582.

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.

Possible Cause:
1) ECM calibration