Very seriously doubt you will get an answer to your "how to repair it?" question.
There are basically two choices: pay Harman the king's ransom they demand, or sell it for parts for a couple hundred and move on. I can see a lot of diyers keen to reuse the case, display and some internals. Yes, it will make a pretty cool project.
I would ask the brand first at the price it is sold, what this NO CODE is refering about before to take a decision.
Digital has evolved a lot, it does not worth to fix it but if it is easy, like a cold joint or a cap to change.
Ah, and if you had a ligthning near the house that caused that, just forget any fix.