Cummins ISB CM850 (2003-06) Fault Code: 1692 PID: SPN: 3234 FMI: 4 Aftertreatment NOx Sensor – Voltage Below Normal, or Shorted to Low Source. Out-of-range battery voltage has been detected by the aftertreatment outlet NOx sensor.

Cummins ISB CM850 (2003-06) Fault Code: 1692 PID: SPN: 3234 FMI: 4 Aftertreatment NOx Sensor – Voltage Below Normal, or Shorted to Low Source. Out-of-range battery voltage has been detected by the aftertreatment outlet NOx sensor.

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:

1)The voltage supplied to the aftertreatment outlet NOx sensor is below + 18-VDC
2)The voltage supplied to the aftertreatment outlet NOx sensor is above + 32-VDC
3)The aftertreatment outlet NOx sensor has malfunctioned or is damaged
4)The aftertreatment outlet NOx sensor internal heater has malfunctioned
5)The NOx sensor part number is incorrect.

On-Board Diagnostics (OBD) information (Euro 4 Stage 1+ Certified Engines):

1)The ECM illuminates the malfunction indicator lamp (MIL) when the diagnostic runs and fails.
2)An engine torque derate will be activated after 50 hours of engine operation with the fault code active.
3)The ECM turns OFF the malfunction indicator lamp (MIL) after 1 ignition cycle that the diagnostic runs and does not fail. The MIL lamp cannot be cleared using INSITE? electronic service tool.
4)The fault code will be cleared from memory after 400 days or 9600 hours of engine operation.

Possible repairs:

1)Replace the NOXx sensor.
2)Replace the aftertreatment exhaust NOx sensor.
3)Clean the terminals and tighten the loose connections.
4)Repair or replace the OEM harness.
5)Replace the ECM.