no display even after changing item Q9400
Hi,
A few weeks ago, my Macbook pro(A1212) stopped displaying. It only showed a white screen, but you could get the display via an external monitor. A friend looked at it and we discovered a burnt Mosfet (SI3443DV) which was item Q9400 on the motherboard. He went and changed it but it only displayed for less than 5 minutes and it went back to the white screen. would you please advice on what to do since i am not in a financial position to take it for repairs at the apple store?
P.s The component is pointed out on the image above.
Joe