Volvo All Engines (2010 Emissions) Fault Code: SPN 3226 FMI 31 PID: PSID 90 Aftertreatment Outlet NOx

The NOx sensor measures the amount of NOx in the exhaust system. The NOx sensor is connected in the J1939-2 data link. This diagnostic trouble code (DTC) indicates a NOx monitoring failure. For example; NOx sensor short- or open circuit, NOx sensor removed, NOx sensor missing signal.

Conditions for diagnostic trouble code (DTC):
1) Abnormal sensor signal

Observable symptoms
1) None

Probable cause
1) Sensor not mounted in exhaust stream
2) Charge air system leakage
3) Exhaust system leakage
4) DEF dosing system
5) NOx sensor
6) EGR Cooler
7) EGR Valve
8) Variable Geometry Turbo

Detailed information
1) The component is not activated only when the ignition is in the ON position, or by starting the engine