The aftertreatment diesel particulate filter (DPF) combustion air valve is controlled by the aftertreatment control module (ACM) output. The combustion air valve is normally closed and is opened when a ground signal is supplied by the ACM to the combustion air valve solenoid. When opened, charged air from the intake manifold is supplied through the combustion air valve to the aftertreatment DPF combustion chamber.

Conditions for diagnostic trouble code (DTC):
1) Exhaust oxygen is too low

Observable symptoms
1) Regeneration not possible

Probable cause
1) Low air pressure
2) Faulty combustion air line
3) Aftertreatment DPF Combustion Air Solenoid
4) Aftertreatment Diesel Particulate FIlter (DPF) Combustion Air Valve