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.
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July 12th, 2007 at 6:22 pm
I need an LCD display (for a desktop, not a notebook.) Since I like hacks and saving money, I figured I would take a display from a really old /broken laptop. I managed to remove a display from a Quantex laptop. The unit I got was missing its bottom and didn’t have a model # on the top, so I don’t know the exact model of notebook, but I do have the numbers for the display, which I removed without damage. The monitor is IBM, model # “ITXG70M,” P/N “83H4500″, EC “FO2812″, and S/N “868953″. The video line coming out of it is not a ribbon cable, but the plugs at each end are thin and wide with a single layer of 20 pins (or holes, rather — the cable is female-female.) If I am looking at the side of the plug that faces upward when plugged into the video board (which piggyback-plugs onto the motherboard,) the colors of the 20 wires coming from the plug from left to right run as follows: Gray w/dark gray stripes || Solid light gray (same as base color on pin 1) || Purple w/stripes || Solid Purple || Solid Blue || Blue w/stripes || Solid Green || Green w/stripes || White w/stripes || Pink w/stripes || Solid White || Solid Pink || Yellow w/stripes || Solid Yellow || Orange w/stripes || Solid Orange || Red w/stripes || Solid Red || Brown w/stripes || Brown. Whew! What a mouthful! There is another cable coming from the inverter, which connects to the display itself with only 2 wires (making perfect sense,) but this other plug happens to have 10 pins, all connected, whose purpose I cannot help but wonder about their purpose. The open end of this plug has 2 layers of 5 holes each. If the plug is oriented the same way as the other one, the wire colors running left-to-right, top-to-bottom are as follows: Purple || Blue || Yellow || Brown || Black -/- next layer -\- White || Gray || Green || Orange || Red. If you know anything about this type of connection, know how I might adapt it to a common monitor interface (like DVI or VGA) or might be able to give me pinouts so I can figure it out myself, it would be appreciated greatly. Thanks.
July 11th, 2007 at 12:33 pm
I have a Dell Inspiron 6000 and thought I had a bad inverter board (screen image was too faint to see much of anything). I took the screen apart and discovered that the cable going to the inverter board had become loose. I re-attached it, put the screen back togethe and bada-bing!, works great now!
I used this link to learn how to take the screen apart and put it back together:
Thought I was going to have to spend hundreds of dollars to repair this laptop and it didn’t cost me a thing!
May 31st, 2007 at 3:00 am
I have the same problem! I think my Sims 2 game is taking up my laptop space, maybe you should delete a big programme. I am selling my Sims 2 games and then buying the sims 2 life stories which is Laptop Friendly. If this doesn’t work. I will need your help!
Jamie.
May 29th, 2007 at 10:40 pm
Matthew,
With a new inverter board your screen worked fine for a long time. I think it’s possible that you purchased a bad inverter board. I would try replacing it again.
If you still having the same problem even after replacing the inverter for the second time, I would probably blame the backlight lamp (located inside the screen).
May 28th, 2007 at 11:53 am
I have a 3 year old Dell 9100 laptop who screen recently when dark. Based on what I read (i.e. you can still see a faint image on the screen) I decided to try replacing the inverter board. I bought a new one off of eBay and installed it. At first everything worked great, and I thought the problem was solved. Then, about 4 hours later, the screen went dark again.
Currently, it will boot up with the LCD on for the first 10 seconds and then it will go black. During the first 2 seconds of booting up, the screen has a pink tint to it. If I close the lid for about 10 seconds and then reopen it, the screen will stay on for about 5 minutes before going out again. This behaviour is similiar to the behavior of the old inverter board, except the close lid trick only provided about 10 seconds of functionality.
Is it possible that there something that is causing the inverter boards to burn out, or could it be that I purchased a bad inverter board? Is the problem something else entirely?
Any suggestions would be appreciated. Thanks.
May 26th, 2007 at 1:06 am
See message : 128
Did,nt find out the problem with my dell laptop.
I rang dell and they replace the motherboard for free, under the warranty.
The call out guy only said it was the motherboard.
How many people have this trouble with a Dell Inspiron 1300
May 24th, 2007 at 8:35 pm
Kefth,
It’s hard to say witch part is causing the problem, it could be the inverter board or the backlight lamp. I would try replacing the inverter board first because it’s much easier and the inverter board shouldn’t be very expensive.
Not sure about that. To me it looks like a faulty inverter board.
May 24th, 2007 at 8:20 pm
Heather,
Did you test the laptop with an external screen? Do you see the same lines on the external display?
If lines appear on both internal and external screens, you have a problem with the motherboard/video card.
If lines appear only on the internal display and the external screen works fine, it could be a bad connection between the video cable/motherboard/screen, defective video cable or failing LCD screen. Reseating the video cable connections might help.
May 22nd, 2007 at 3:20 am
I have a Sony Vaio PCG-GRZ615 model for about 4 years. I experienced no problems, until yesterday when my LCD screen fickered two three times and then went off. However, I can still see a dim image on my LCD screen. I attached an extranl CRT monitor and everything and it works well. So no problem with the graphics card I pressume.
As far as I leart searching the internet my problem can be either a converter or a CCFL lamp problem.
I opened up the lcd screen and I am wodering the problem lies; IS IT A CCFL or a CONVERTER PROBLEM?
I give you one extra element that might with some extra help. When I press the lid switcher manually with a pen the CCFL light tries to light for a sec (yellow-red color) and then again goes off. This happens every time I press the lid switcher.
I know that when the converter starts working it gives a greater voltage supply for a second. So my question is… if the CCFL lamp was the problem would it flicker at all every time I press the lid switcher or it it will be just dead at all times?
Any suggestion would be appreciated.
Thank you
May 21st, 2007 at 5:37 am
I have the same problem as the guy who left comment 57, but the screen isn’t totally blank yet. It’s just covered with lines. How can I fix it? Thanks