Cummins ISX15 CM2250 (2010-12) Fault Code: 3718 PID: SPN: 3216 FMI: 13 Aftertreatment Intake Nox- Out of Calibration

Circuit Description
The aftertreatment intake NOx sensor is a smart device and receives commands from the ECM via the J1939 data link. The aftertreatment intake NOx sensor performs its own internal diagnostics and reports malfunctions back to the primary ECM using the J1939 data link. The NOx sensor is permanently attached to the NOx control module. They are serviced as single component and can not be replaced individually. The aftertreatment intake NOx sensor is used to measure the engine-out NOx emissions.

Component Location
The aftertreatment intake NOx sensor is mounted on the engine near the turbocharger turbine outlet.

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
A mismatch has been detected between the engine’s electrical system voltage and the NOx sensor voltage rating.

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.
Conditions for Clearing the Fault Code
To validate the repair, start the engine and let it idle for 1 minute.
The fault code status displayed by INSITE? electronic service tool will change to INACTIVE immediately after the diagnostic runs and passes.
The ECM will turn off the amber CHECK ENGINE lamp after the diagnostic runs and passes.
For On-Board Diagnostic (OBD) engines, the ECM will turn off the MIL after three consecutive trips where the diagnostic runs and passes.
The ?Reset All Faults? command in INSITE? electronic service tool can be used to clear active and inactive faults, as well as extinguish the MIL for OBD applications.

Shop Talk
Possible causes of this fault code include:

Calibration incompatibility between aftertreatment intake NOx sensor and ECM calibration
System voltage is incorrect for the installed aftertreatment intake NOx sensor part number
Incorrect aftertreatment intake NOx sensor is installed in exhaust system.
Reference the appropriate original equipment manufacturer (OEM) wiring diagram when troubleshooting circuits that utilize wiring supplied by the OEM.

For intermittent power supply and data link 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) Aftertreatment intake NOx sensor failure
2) ECM calibration