Here is a simple diagram that will help you to understand how a notebook display assembly works and how an image appears on the screen. I’m not an artist and I tried my best drawing this diagram, so if you cannot see a laptop in this picture, don’t be mad. 
A generic display assembly includes a very few parts and knowing them will help you to understand witch part can cause a problem if you laptop video not working properly.
Video cable. A video signal from the motherboard goes to the LCD screen through the video cable. The video cable connects to the motherboard (or video card) through the connector 1. The video cable connects to the LCD screen through the connector 2. The video cable (in most cases) is also responsible for supplying a necessary voltage for the FL inverter board. The video cable connects to the FL inverter board at the point 3.
FL inverter board. This board is responsible for converting low voltage DC power (point 3) to high voltage AC (point 4), necessary to light up the backlight bulb. If the FL inverter board is bad, the LCD screen (backlight bulb) will not light up when you turn on the laptop, but you still should be able to see a very dim image on the screen.
Looking for a new screen, video cable or inverter board? Find it here.
CCFL (backlight bulb). When the backlight bulb lights up, you can see an images on the LCD screen. In most cases the backlight bulb is a part of the LCD screen and if it’s bad, the entire screen has to be replaced. By the way, some specialized repair shops can replace the backlight bulb itself.
Lid close switch. The lid close switch is a small button that locates close to the display hinges. On some newer models there is no button, because the switch is magnetic. You can set up your laptop to go to a hibernation mode or to a standby mode when the LCD is closed. It’s done through power management software. These modes are triggered when the display is closed and the lid close switch is pressed down. If the LCD screen on your laptop will not light up when you open the display assembly, check the lid close switch is stuck inside (it might happen because the switch is dirty).
Related articles:
Fixing notebook video problems.
If you find this article useful, please consider making a donation to the author. Thank you!
May 1st, 2008 at 1:52 pm
Toshiba M105 – S3064 Notebook, Video dissapears at random (doing nothing, searching the internet, etc) I found that it does the same on another monitor, the bulb is lit, no picture, somtimes the colors are all black, except for the bulb lit at botom, white, red, blue, green. I tried shifting between notebook and monitor using FN +F5 it has 3 settings, my notebook, both, and other monitor, when working right it can be seen that way, the notebook only, or both notebook and monitor, or monitor only, when not working right it can only be seen when in both setting on notebook not monitor too.. I can erase the hard drive with sofware all day and screen will remain visible
April 29th, 2008 at 7:42 am
I was wondering if anyone can help me with my Fujisu siemens life book laptop . It will not turn on . I brought a new charger , but still it dose not work . Can anyone tell me how can I fix it myself please ?
April 19th, 2008 at 1:35 pm
ngarmadji elie,
Check out this category with links to service manuals, you may find instructions for your laptop in there.
April 18th, 2008 at 5:29 am
i need help about how to dismantle laptop and how to assemble it
April 14th, 2008 at 1:58 am
My HP Pavilion’s screen has been acting up this weekend, Saturday morning the screen came on, but dim, for a few minutes, but I rebooted it ten minutes later and it worked fine all day. Today, the screen was dim again when it turned on but failed to lighten at all. Thinking it could’ve been cause by contact with a liquid or something, I dried it out with a blow dryer for thirty minutes and then it rebooted fine again, but I turned it off and am letting it dry until tomorrow to be safe. Anyone have any ideas what could be the cause?
March 31st, 2008 at 6:35 am
I just replaced a lcd screen for a compaq nc6230 that was ran over with auto sreen is showing 4 small sreen in reverse. Did not change inverter. Should I? Please help.
March 27th, 2008 at 12:29 am
I have one Acer Aspire 1804WSMi where after two years of use apper in the Dysplay two targes one Black and other White I lose half of display. What can I do to repair this problem ? Thanks Carl.
March 8th, 2008 at 11:25 pm
Dave Rouse,
There is a good chance that replacing inverter will fix the problem.
Here’s an example of replacing inverter board on an IBM ThinkPad laptop.
Screen inverter replacement.
It’s much harder to replace the backlight lamp. Here’s an example.
How to replace laptop backlight lamp (CCFL)
March 7th, 2008 at 11:53 pm
I have a HP laptop 1610 modle and my LCD screen has gone dark
where I can hardly see an image. I tried pressing FN+F4 and nothing changes at all. I believe it may be a bad inverter board or
backlight gone bad. How do I go about replacing the inverter or the backlight on a laptop LCD screen so I can fix the problem.
Please help !!
February 25th, 2008 at 6:40 am
I’m having problem with the video of my compaq evo n1000v laptop.
And I’m planning of re-flowing the gpu chip. Can somebody show me where can I find the gpu chip of this specific brand. I’ve open the keyboard and the palmrest but i didn’t see the ati radeon chip.