Resolved Macbook a1181 won't turn on

I am trying to fix this for a friend. It is a white macbook, I don't know for sure whether its an a1181, the writing on the bottom is rubbed off the case. When you hit the power button it will get to different stages of the start process, but it doesn't stop at the same spot consistently. sometimes I can log on and start toying with it, other times it will get to the apple screen and stop, and still other times there will be just nothing. any help will be appreciated, thanks

I don't know if it is related, but I also just fired it up and got it working, but then the backlight went off.

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I have tried those, can't really do any of them because I have no screen, and the computer won't boot far enough to do them.

No I haven't opened up the topcase, what specifically do you think I should be looking at/for?

I opened it up and don't see anything strange. I forgot to mention though that the battery does not charge, could be a bad battery though, I don't know

the weird thing about it is that the when you press the indicator button on the battery it does not blink at all. different magsafe adapters have made no difference. I got a new magsafe board so we will see what that does.

I replaced the magsafe board and that seems to have done the trick. on a side note, I installed coconut battery on it after I got it up and running and it says that the battery is at 0% of original capacity. so the battery not charging was a separate issue.