I'm Alessandro from Italy Rome and in the past I had a lot of issues you can find in this post, now they seem solved, really a lot things done and it should be hard understand what it worked.
For sure I always follow what I found here.
Thanks for all the help!

This time the main issue is the radiator fan who start and never stop. Probably the cause as I can see upper, it could be a dead battery.
I changed the fan relay and the mechanic tried different things but it seems impossible to solve.
Any other help will be really appreciated, thank you in advance!