Cummins ISB4.5 CM2150 Fault Code: 1692 PID: SPN: 3234 FMI: 4 Aftertreatment NOx Sensor – Voltage Below Normal or Shorted to Low Source.

Circuit Description
The aftertreatment outlet nitrogen oxides (NOx) sensor is a smart device and receives commands from the engine electronic control module (ECM) via the J1939 data link. The aftertreatment outlet 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 outlet NOx sensor is used to measure the outlet NOx emissions from the engine.

Component Location
The aftertreatment outlet NOx sensor location can vary depending on engine application. It is usually located in the exhaust system at the outlet of the aftertreatment catalyst.

Shop Talk
The NOx sensor is permanently attached to the NOx control module. They are serviced as a single component and can not be replaced individually.

Possible Causes
-The voltage supplied to the aftertreatment outlet NOx sensor is below + 18-VDC
-The voltage supplied to the aftertreatment outlet NOx sensor is above + 32-VDC
-The aftertreatment outlet NOx sensor has malfunctioned or is damaged
-The aftertreatment outlet NOx sensor internal heater has malfunctioned
-The NOx sensor part number is incorrect.

On-Board Diagnostics (OBD) information (Euro 4 Stage 1+ Certified Engines):
-The ECM illuminates the malfunction indicator lamp (MIL) when the diagnostic runs and fails.
-An engine torque derate will be activated after 50 hours of engine operation with the fault code active.
-The ECM turns OFF the MIL after 1 ignition cycle that the diagnostic runs and does not fail. The MIL lamp cannot be cleared using INSITE™ electronic service tool.
-The fault code will be cleared from memory after 400 days or 9600 hours of engine operation.