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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November 29th, 2006 at 7:14 am
This helped me a lot.
On my laptop, the FL inverter going bad haven’t made the light just dim, but totally black. It would only be visible by reflecting some external light on it, such as ambient or a flashlight (with that I can even work a little on it).
Anyway, maybe you should add that, at least as far as my research went from here, most of the cases when you can still see an image with no backlight, it is FL inverter problem, since it’s really rare for the CCFL to go bad.
What I don’t understand is why regular LCD monitors (for desktops) doesn’t give so many problems as laptop does. Maybe they don’t use FL inverters…
November 28th, 2006 at 1:35 pm
[...] I think that you might have a faulty FL inverter board. Take a look at the laptop display assembly diagram. The backlight bulb lights up when it’s getting enough power form the FL inverter board. The inverter board acts as a power supply for the backlight bulb, it converts low voltage DC power to high voltage AC power. If there is something wrong with the inverter board, the backlight will not light up. I think the high pitch noise is coming from the FL inverter board and I would try replacing this board first. Here’s guide for taking apart the display assembly on a Satellite A65 laptop. It’s not for your laptop, but all steps should be pretty similar. If you follow steps 1-6 you should be able to replace the inverter board yourself. If you are not confident, take the laptop to a repair shop because you can damage it. BTW, when you have a faulty display inverter board, you still should be able to see a very faint image on the laptop screen. Can you? [...]
November 26th, 2006 at 6:21 pm
Jeff,
Even if you have a bad inverter or bad backlight bulb, you still should be able to see a faint imaged on the screen. Can you see a faint image after the screen goes black? If yes, then probably you have a failed inverter board. Yes, it could be a bad backlight bulb but I would replace the inverter first, because inverter board failures are more common then backlight bulb failures. Here’s Dell Inspiron 6000 service manual, it has laptop disassembly instructions. I don’t think that there is an online hardware diagnostic that can help you to narrow down the problem. The only way I know is replacing the inverter board and see if it fixes the problem.
I don’t know. I think it would be a good idea to open up the display assembly, find a part number on the inverter board and search for a replacement by the part number.
The backlight bulb is located inside the screen. I’ve never replaced the bulb myself but some companies offer this service. I replace the entire screen.
Usually a failed video card would affect the video output on both screens – laptop LCD and external monitor. You mentioned that the external video is fine, so I assume the video card works fine.
November 22nd, 2006 at 7:53 pm
I have a Dell Inspiron 6000. It starts up well but usually at the point I type in the password it goes dark. Get a good picture when I hook it up to another monitor. If the bulb is bad would I see all the windows start up? If it is the inverter I have the same question… I live in the jungle of Indonesia so taking it in for repairs is not reasonable. Is there an online hardware diagnostic out there? Would like to do a cheap fix here. Looking online for possible parts….are all Inspiron 6000 inverters compatible? Is there a way to know if something found here is compatible? If it’s the bulb, it’s hopeless right? Could it be the video card? Like only part of it fried?
November 14th, 2006 at 2:14 pm
I have a dell inspiron 1300 and the entire right hand side of my screen is busted! How much will the repair/replacement cost? And where do I take it?
November 10th, 2006 at 1:21 am
i was wonder can you hook up a labtop lcd to an dvd player?
November 7th, 2006 at 8:16 am
I have a Dell 9300 that I have ordered a replacement lcd for after line started developing randomly over the past month. For laughs, I called Dell to see what they would charge to fix it.
They gave me a 499.00 figure to replace the lcd and “run diagnostics” on the laptop to tell me of any other problems. *Note: No other problems if found would have been covered under that 499.00 price tag..that was just for them to replace the monitor and check everything out.
I bought a replacement lcd online for 230.00 and did it myself. Shop around a bit and you can find a lcd at a decent price and do it yourself. This isnt hard, just take your time and have a small screwdriver!
November 1st, 2006 at 8:20 pm
Mark,
Did you test the adapter itself? May be it’s bad?
November 1st, 2006 at 2:14 pm
i need help on how 2 fix the dell latitude cpi when i try n switch it on nothin happens and the batty wont charge and when i plug the charger in nothing happens can you help me plz email me back on how 2 fix this problem and what i can do? txt back mark
October 24th, 2006 at 10:27 pm
Kirish,
You’ll have to replace the entire screen not just repair it. If you decide to replace it yourself, you can use this Dell Inspiron 6000 service manual. The best price for a new screen you can find here, just search for “Inspiron 6000 screen”. You can find one for about $230-250.
If you take it to a laptop repair shop, you will have to pay $100-120 for labor plus a new screen. The screen will be more expensive if you buy it through the service center.
There is another option, you can call directly to Dell and ask them. I have no idea how much they will charge for the screen replacement.