The following advice may be useful for any owners of late model Skoda diesels who are considering having them remapped.

I am not a technician but have been following this process with my own vehicle, and have done a bit of research on the subject.

Since about 2009 (I think) some versions of the ECUs have encryption which makes it difficult to remap the ECU via connecting to the OBDII port, which is currently the main method of remapping. It is still possible to do a remap by taking the ECU out and reflashing it on a benchtop with specialised equipment. However I would consider that this entails a higher degree of technical expertise along with potential risk to the ECU.

The encryption from what I've read seems to be mainly an issue with the diesels, and VAG don't yet seem to have brought it in for the majority of their petrols. However I would think that it is only a matter of time. As for VAG's motivations in doing this, that seems pretty obvious, but others may want to add some discussion on this.

In the meantime if you have a late model diesel and are thinking of getting it remapped, find out first whether the ECU has encryption and think hard about whether it is actually worth it.

its not just difficult to remap a current encrypted ECU via OBD, its currently impossible and cannot be done. Until the encryption key is cracked (currently unlikely), the only solution is bench flashing.

My 2010 1.8 TSi Octavia is definitely encrypted.

Shark Performance covered this pretty well in November last year:

EDC17/MED17 (2.0TDI Common Rail / 1.8/2.0TSI) tuning protection explained.

Yeah this is old news