Korg Forums

Many thanks, at the end someone on the Internet that summarized all the necessary actions.
Will try and report

Impressive

Oops...

Not bad as a new user and for the very first post...

But at the end at least it seems I was right suspecting about the cables

Seems to me that you've disconnected part of the EX memory module or the whole flat cable that connects the memory card to the motherboard... double check if the KLM-1385 card is firmly connected and the flat white cable near the battery: http://hem.fyristorg.com/krall_online/egna/KorgT3/battery ...