[sam1er]

The errors appeared for a reason, so there's got to be an issue somewhere or the car is not being used regularly on the motorway hence the build up and codes coming. I had a problem with my 330d not regenerating due to Thermostat not reaching proper temps and a dodgy EGR pressure converter. Once those were resolve, i cleared the codes and used some forte treatment the issue has not reappeared.

The car does 2 types of regens i believe. Passive and active. Passive is always running even when you have errors. Active will only run once you reach a certain soot level and if there is nothing stopping the process form engaging e.g. low fuel, errors related to EGR or back pressure or temp not reaching up to required levels.

The soot levels once a regen are done are predicted values initially, the real values update after a short while, hence you see once a regen has been performed the soot levels go right down then they slowly creep back up again to a number then settle down and increase slowely at the expected rate. If your DPF is not clearing correctly then there could be a problem somewhere e.g. dodgy sensor or faulty/clogged EGR. (This is all what i found after having read alot of articles on the net about how the DPF system works and even then information is very limited and fragmented)

Try a rescan after a couple of days and see if any of the errors return.

Particular combination of codes but also seeing which codes appear first can lead you to the issue causing the problem. Even though my garage kept thinking the problem was fixed, using carly app and google i managed to find the source of the problem and get them to fix it accordingly. In my case the EGR code was triggering the other DPF related codes due to the dodgy pressure converter and some perished vacuum hoses. I had to run live logging to check my exhaust temps and coolant temps plus monitoring and clearing fault codes on the fly whilst driving to help pinpoint the issue i was having.