PS1 5002 disk drive not spinning

Hi everyone, I've got a PS1 that I believe has some board problems.

Basically the disk drive doesn't spin at all, doesn't matter what I do, I don't get any reaction.

I've tried to clean the lens, replace the disk drive (with a working one tested on another console) but no luck… I've also tried to install an xstation thinking that it would solve the problem, which obviously didn't change anything (the xstation in now installed on another device which is working just fine).

Doesn anyone have any idea on what could it be wrong? I've searched everywhere on Google and iFixit, but it doesn't seem that anyone had this problem before…

Thank you.