Cummins X15 CM2350 X116B Performance Series (2018 & Newer) Fault Code: 6721 PID: SPN: 5569 FMI: 0/16 Aftertreatment 1 Diesel Particulate Filter 1 Soot Sensor ECU Internal Temperature – Data Valid But Above Normal Operating Range – Moderately Severe Level

Lamp:
Amber

Reason:
High internal temperature detected in the aftertreatment diesel particulate filter soot sensor module.

Effect:
None on performance.

Circuit Description:
The aftertreatment particulate matter sensor is a smart device and communicates with the Engine Control Module (ECM) via the J1939 data link. The aftertreatment particulate matter sensor performs internal diagnostics and reports malfunctions back to the primary ECM using the J1939 data link. The particulate matter sensor is permanently attached to the particulate matter control module. They are serviced as a single component and can not be replaced individually. The aftertreatment particulate matter sensor is used to measure the soot emissions at the outlet of the aftertreatment system.

Component Location:
The aftertreatment particulate matter sensor location can vary depending on engine application. It is usually located in the exhaust system at the outlet of the Selective Catalytic Reduction (SCR) catalyst.

Conditions for Running the Diagnostics:
This diagnostic runs continuously when the engine is running.

Conditions for Setting the Fault Code:
The aftertreatment diesel particulate filter soot sensor module reported the internal circuit board temperature was too high.

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:
1. To validate the repair, start the engine and let it idle for 1 minute.
2. The ECM will turn off the amber check engine lamp immediately after the diagnostic runs and passes.
3. The fault code status displayed by the recommended diagnostic tool or equivalent will change to inactive immediately after the diagnostic runs and passes.
4. 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.
5. The “reset all faults” command in the recommended diagnostic tool or equivalent can be used to clear active and inactive faults, as well as extinguish the MIL for OBD applications.

Shop Talk:
This fault code indicates the internal temperature of the aftertreatment diesel particulate filter soot sensor module was too high. Troubleshoot the exhaust system for leaks, missing heat shields, or dirt and debris that could lead to overheating of the aftertreatment diesel particulate filter soot sensor module.