Laptop suddenly shut down won't charge nor turn on.

@shenbagaoisan there is always a possibility that your processor or the RAM has failed. We do not know exactly what was checked but if proper determination was made, to check if the motherboard received power but did not turn on. Depending on the exact motherboard, schematics and board-view files might be around. Those area must-have for a board repair. Repairing a board can be relatively simple (bad power fuse or FET comes to mind) or incredibly complex. That of course requires to have proper tools and experience to repair.

As you can see, there really is no easy, straightforward answer. It's all step, by step, by step. If you can give us your exact logicboard number (it is printed on the board, most common on the side that faces the keyboard) then we can see if the schematics are available.