System Components

The reductant tank stores the reductant.

The reductant tank filler hose is a 2-piece design consisting of a filler hose and a vent hose.

The reductant pressure line supplies the reductant from the reductant pump assembly to the reductant injector. There are different reductant pressure lines for different vehicle wheelbases. The reductant pressure line is heated to prevent freezing.

The reductant pump assembly pumps reductant to the reductant injector. It contains a diaphragm pressure pump, pressure sensor, purge valve, outlet filter, and internal heating element.

The reductant heater and sender assembly contains the pickup tube for the reductant pump module, electric heating element, temperature sensor, and electrode-type level sensor.

The reductant injector is a Pulse Width Modulated (PWM) solenoid controlled directly by the PCM. The injector receives reductant from the reductant pressure line and sprays it into the exhaust stream, where it is mixed into the exhaust gases before entering the catalyst.

The NOx sensor detects levels of NOx in exhaust gases and sends input to the NOx sensor module. For additional information, refer to ELECTRONIC ENGINE CONTROLS - DIESEL ENGINES .

The NOx sensor module receives input from the NOx sensor and sends it to the PCM. For additional information, refer to ELECTRONIC ENGINE CONTROLS - DIESEL ENGINES .