MacBook Pro 2.5 intel don't start

Hi! Your English is great! Thanks for the video!

In addition to resetting the PMU/SMC as you have done, I would try resetting the PRAM, i.e. hold down option-Apple-p-r as you power on the machine. The screen should stay black, and it should make the chime sound after about 10 seconds.

I would also remove the battery, do the resets again, and see if that makes a difference.

I would test the memory and memory slots by removing one module (so that there is only one left, then doing the resets again, and then moving the module to the other slot (so the first slot is empty), and doing the resets again.

I would shine a flashlight through the Apple symbol from the back of the screen. If you see a faint image, you're probably dealing with a backlight issue. I would also connect the machine to an external display...if you get an image on the external display, that confirms the laptop is mostly functional and you probably have an issue with one of the screen components. If you don't get an external image at all, it's more likely be a logic board or DC-in issue.

Let us know how it goes!