A Laptop Powering On But With No Backlight successfully  Repaired

 

 

 

 

 

 

 

A university student who needed this laptop urgently brought it to my shop for repair and the main problem was no back light on the screen.

A very simple way to identify a back light issue is to shine a light over the screen and you will see what is being displayed.

I know the photo is out of focus but if you look carefully into it you would see a dim logo of the laptop being displayed.

There could be many reasons for dim display; it could be a bad screen, bad back light board or could be the screen socket on the board itself.

In my case was the main screen connector on board because when I touched the screen flex cable a brief flash of light appeared and then disappeared which could be a bad flex cable or the socket itself.

When checked through my microscope I found a lot of cold and bad soldering joints on that socket and that require a micro soldering job. I got the flux tube out and with a temperature of 400 and air flow of 60 set on my heat station I started gently to heat up the connected after adding the flux on it. To make sure all the soldering joints are connected firmly on board, I touched the socket pins with my flat soldering tip after adding good amount of flux and when the job was done, I let it cool down, clean it with IPA and assembled the screen and hoped for the best.

The screen is alive again but I could see another problem with it but all was well after clicking the restart my PC option and it came on nice and neat.

The customer was happy when I informed him of the repair and he rushed to pick it up because on that laptop he had a lot of information that has to do with his graduation thesis. I was glad I could help out in his matter and to that I could say... conclusion : if I were to found all the connection ok then I could trace the led driver output voltage and also the backlight condition .