Volvo All Engines (2010 Emissions) Fault Code: SPN 3556 FMI 14 PID: PPID 329 Aftertreatment Doser

The Aftertreatment Hydrocarbon Dosing Module contains three non serviceable valves, the Aftertreatment Fuel Shutoff Valve, Aftertreatment Purge Air Valve and Aftertreatment Hydrocarbon Dosing Valve, and a serviceable Aftertreatment Fuel Pressure Sensor.
During DPF regeneration the Engine Control Module (ECM) sends a voltage signal to activate the Aftertreatment Fuel Shutoff Valve to the open position. This allows fuel to flow into the Aftertreament Hydrocarbon Dosing Module. The Aftertreatment Fuel Pressure Sensor monitors the fuel pressure value and sends a reference signal to the ECM. The ECM then sends a PWM signal to the Aftertreatment Hydrocarbon Dosing Valve that regulates the amount of fuel delivered to the Aftertreatment Hydrocarbon Doser through the air/fuel line.
During Air Purge operation the Engine Control Module (ECM) sends a voltage signal to activate the Aftertreatment Purge Air Valve open. This allows air pressure to flow into the Aftertreament Hydrocarbon Dosing Module. The ECM then sends a PWM signal to the Aftertreatment Hydrocarbon Dosing Valve that allows purge air pressure to be monitored by a signal from the Aftertreatment Fuel Pressure Sensor to the ECM.

Conditions for diagnostic trouble code (DTC):
1) Aftertreatment Hydrocarbon Doser, Leakage

Observable symptoms
1) Regeneration not possible

Probable cause
1) Aftertreatment Hydrocarbon Doser
2) Fuel line(s), Leakage