Cummins ISX11.9 CM2250 – Service Manual Diesel Exhaust Fluid Usage – Abnormal

Symptom Tree  t128

This is symptom tree t128
Cause Correction

Use this TS tree to troubleshoot complaints of low or high diesel exhaust fluid usage.

Electronic fault codes active or high counts of inactive fault codes

View and troubleshoot the fault codes with INSITE™ electronic service tool. Refer to Section TF in the Fault Code Troubleshooting Manual, Bulletin 4022225.


Aftertreatment diesel exhaust fluid leak (external)

Inspect for external aftertreatment diesel exhaust fluids leaks near the aftertreatment diesel exhaust fluid tank, aftertreatment diesel exhaust fluid lines, and associated connections. Repair or replace parts as necessary.


Aftertreatment diesel exhaust fluid low level or warning level not set correctly

The vehicle manufacturer has the ability to change the settings for low warning activations, causing the low diesel exhaust fluid level warnings to activate earlier than expected. Verify the settings are correctly set. Refer to the OEM service manual.


Electronic control module (ECM) calibration is malfunctioning

Verify that the electronic control module (ECM) calibration is correct. Check the calibration revision history for applicable fixes to the calibration stored in the ECM. Refer to the calibration history spreadsheet Click here to see ecm_calibration_rev_history.xls

on QuickServe™ Online Internet Website or the INCAL™ calibration CD. Compare the calibration stored in the ECM with the engine rating and the Control Parts List (CPL), Bulletin 4021328. If necessary, calibrate the ECM. Refer to
Procedure 019-032 in Section 19


Aftertreatment diesel exhaust fluid level gauge is inaccurate

Verify that the aftertreatment diesel exhaust fluid level gauge is correctly calibrated and matched to the diesel exhaust fluid tank. Refer to the OEM service manual.


Engine out NOx emissions above normal

Refer to the Engine Performance Troubleshooting Tree in Section TT.

Last Modified:  09-Jul-2010