VWG haven't used flash codes since the likes of the MK2 VW Golf, I don't think any Seat built under VWG control has ever used them.
I worked for Seat when the Altea was launched. The introduction of more frequent CAN systems being used led to the introduction of the second generation of VWG computer based diagnostic machine - the VAS 5051B, with it's predecessor being the VAS 5051. A windows based computer running VWGs software "VAS-PC". It produced fault codes, descriptions then test plans based on what codes were read. That was over 20 years ago, not much has changed in terms of fault code reading, only the complexity of the systems involved and the skills required to find faults when they occur.
Probably my
dealers training at the time. Finger in the air. That Altea's electrical control box that costs a fortune to replace... they never replaced it. The issue went away.
The other issue where a different
dealer super glued the turbo boost pipe on when the clip broke and it blew off gives me a dim view of
dealers. The radio advert motto was "people you like to do business with". Nope. That
dealership went out of business. I know what they did since they offered me that fix after the smoke test, after it blew off on starting car up and they said they had no clips in.
Two electrical faults that fixed themselves and the turbo boost pipe blowing off were the only issues I had with the Altea. Not a bad car for it's time.
Edit. Not forgetting the AC that use to pack up under heavy load on hot days. Solution was to turn ignition off, pull the AC fuse, push back in and restart. All was good again. That saved circa £600 on getting the unit changed.
& ofcourse the paper speakers it came with:
OK I said I would report in detail on my "Altea Speaker Project" once I got it connected up. I should thank Paul on Alt54 for his advice and replies to question when I asked him stuff about what he did. Paul said that you could replace them with 17cm ones but since I wanted Infinity speakers...
www.seatcupra.net
Good thing about Vag infotainment if they were called that in the day, 20 years ago, the amplifiers were very good but let down by useless speakers. Has it been 20 years... must be getting old

. 20 years later Cupra models can be got with proper branded speakers not unbranded paper ones....
The Altea Sport had good bucket seats.