MacBook Pro unibody 13'' 2.56Ghz Mid 2009 No Backlight on LCD

Hi I have my macbook pro 13'' unibody mid 2009 with no backlight on LCD.

everything works on the macbook pro apart no backlight but if using an external monitor it works.

I am trying to understand how to check some of the common parts that might cause the issue using a multi-metre.

1) The fuse: A very tiny component showing a little dot in the middle located not far from WLED

*What value should i get when the mac is powered?

• I have check for continuity it's not open (so i believe is good)

2) the WLED driver: a square chip located very close to (next to) the LCD backlight cable.

*How to check it when the mac power off (check for resistance)

*I am a little bit confuse when reading the serial on the part (VM96AF-L85433Q I think) but on the web they talking about LP8543 made by Texas Instrument.

Is that the same part?

As soon I i believe what's maybe wrong I plan to buy the part and find a professional to install it for me hoping to save my macbook pro.

Thanks for all your support