There are currently three types of the regeneration process; Spontaneous, Dynamic & Service.
Spontaneous Regeneration happens when the DPF reached 600 degrees Celsius. If this type of generation does not occur and the ECU calculates that the DPF has reached its storage capacity, the ECU will initiate a Dynamic Regeneration.
Dynamic Regeneration is indicated by a continual DPF light illumined on the dash. The vehicle must keep running in order to complete the dynamic regeneration. If the vehicle is stopped, the dynamic regeneration will commence once again when the vehicle is run again. If the dynamic regeneration is stopped too many times, the DPF light illuminated on the dash will start to flash. This means a service Regeneration is now required at an Automotive Workshop.
Service Regeneration is conducted via a scan tool at an Automotive workshop. Extra fuel can be added via a services of injection pulses. This increases the exhaust gas temperature to the required 600 degrees Celsius in order to burn off the particulates/soot. If the flashing DPF warning light is ignored, it may cause the DPF to block up beyond serviceability and require replacement. The differential pressure sensor readings can be read via the scan tool, which will determine in the service regeneration has or has not been successful. A dynamic regeneration normally follows a service regeneration.
The purpose of the exhaust gas recirculation system is to reduce the amount of Nitrogen Oxide (NOx) emissions in both petrol and diesel engines by up to 70%. The is done by recirculating exhaust gasses to help bring the peak combustion chamber temperatures down.