Do you have a problem with the backlight on your laptop? If yes, you are not alone, that’s one of the most common laptop problems. In most cases the screen inverter is the culprit. Here are some LCD screen backlight failure symptoms that could be related to a bad inverter board:
- Laptop boots as usual but after some time the screen blacks out. You still can see an image on the screen but it’s very dim. You might even use a flashlight to see it better. Sometimes the backlight comes back for a while but then goes off again. In some cases you can turn the backlight on if you tap rapidly on the lid close switch.
- The screen always stay black and the backlight never comes on but you still can make out an image on the LCD. It’s dark, but the image is still there.
-In some cases you might hear a buzzing noise coming from the area where the inverter board is located, it’s on the bottom part of the display assembly.
NOTE: if you cannot see an image on the screen, most likely you have a different problem and there is nothing wrong with the screen inverter.
Other related articles:
Laptop has bad video on the LCD screen. What is wrong?
Notebook display assembly diagram. How image appears on the screen.
How to troubleshoot and fix laptop video problems
How to replace laptop backlight lamp (CCFL)
Here’s an example of replacing the FL inverter board on an IBM ThinkPad T41 notebook. This guide will work fine for any other IBM notebook. Replacing screen inverter on other notebooks like Dell, HP, Toshiba, etc… will not be much different.
First of all, unplug the AC adapter and remove the battery.
In order to access the inverter board you’ll have to remove the LCD screen bezel. On most laptops screws are hidden behind screw seals. In this case we have 5 screw seals on the front. Carefully remove the seals with a sharp object and glue them on the LCD bezel, in this case you will not lose them. Remove all screws and mark them somehow so you are not confused when you assemble the notebook back.
Some laptops also have screws on the side of the display. This notebook has 3 screws on each side. Remove screws seals and then remove screws.
Start removing the LCD bezel with all fingers. Carefully wiggle the bezel to release plastic latches. Never use any sharp object during disassemble because you can accidentally damage the screen.
If latches are very tight you can use a guitar pick to unlock them. Insert the guitar pick between the LCD bezel and cover and carefully move it alone the side.
This notebook allows you to replace the inverter board without removing the LCD bezel completely. Lift up the bottom part of the bezel and remove one screw securing the inverter board to the LCD cover. This location is very common for the screen inverter. On most laptops you’ll find it under the display bezel below the screen.
Carefully lift up the FL inverter and rotate it a little bit. Unplug cables on both sides. The left side of the inverter board connects to the video cable, the right side to the backlight bulb (CCFL tube) inside the LCD screen. Remove the inverter and replace it with a new one.
To find a new inverter board (and any other spare part too) for any IBM notebook you should use the FRU number from the part.
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November 5th, 2009 at 9:55 am
November 2nd:
The LCD no longer lights up but stays black. With a flashlight I can just barely see the display. I replaced the LCD inverter per your instructions and that did not fix the problem. I just finished replacing the backlight and that did not fix the problem either. Any idea what else could be the problem?
I assume that parts you installed are good.
Take a look at the lid close button if you have it on your laptop. It’s a small button located somewhere close to one of the hinges. Make sure the lid close button moves freely. Sometimes, the button might get stuck inside the case the laptop “thinks” that the display is closed even though it’s opened. Try tapping on the lid close button.
November 5th:
When I press the lid close button the laptop goes into sleep mode, so I don’t think the button is “sticking”. Right? I do remember that when I first started having the LCD display problem, pressing on the lid close button would cause the screen to light up and function normally for up to a couple of hours. However, that only worked for a day or so, and now pressing the lid close button has no affect on the LCD lighting.
November 5th, 2009 at 9:51 am
Hi, Can anyone help me?
I have a Dell XPS out of warranty.
The screen sometimes changes the color black for red. It is not changed 100% but 80%.
I already tried a connection with another screen and it worked well.
Do I have to replace the screen or is it a problem with this inverter?
Thank you
November 4th, 2009 at 8:33 pm
adl,
It’s possible that there is a problem with laptop memory.
1. Try reconnecting memory modules.
2. Try removing memory modules one by one. Test the laptop with each module separately.
3. Try installing new memory module.
November 3rd, 2009 at 9:21 pm
Hi
i need help please i have vaio sony laptop yesterday was working fine but this morning when i turn it on i can see the light on but nothing show in the screen i just hear the fan working
how can i fix this, i am worry if i took it to technical i will lose what i have in my computers, all my work in the laptop i did not put in external memory!!!!
any solution please
November 2nd, 2009 at 4:26 pm
Bill,
I assume that parts you installed are good.
Take a look at the lid close button if you have it on your laptop. It’s a small button located somewhere close to one of the hinges. Make sure the lid close button moves freely. Sometimes, the button might get stuck inside the case the laptop “thinks” that the display is closed even though it’s opened. Try tapping on the lid close button.
October 31st, 2009 at 5:36 pm
Dear Laptop Repair Guy… Thank you for the marvelous information. I have an Acer Travelmate 4652 LMi that exhibits all the backlight symptoms you have described. The LCD no longer lights up but stays black. With a flashlight I can just barely see the display. I replaced the LCD inverter per your instructions and that did not fix the problem. I just finished replacing the backlight and that did not fix the problem either. Any idea what else could be the problem? Thanks!!!
October 29th, 2009 at 9:18 pm
nick,
It’s hard to tell what is going on without testing the laptop.
Take a closer look at the screen when the light goes out? Can you still see a faint image on the screen? If yes, most likely you have a failing inverter board.
If a new inverter doesn’t fix it, it could be bad backlight lamp inside the LCD screen.
October 29th, 2009 at 9:12 pm
Eric,
Do you have a sticker on the original inverter? Maybe you can find the part number and google it?
October 27th, 2009 at 2:53 pm
I need a new power inverter for my Gateway NX260X, but nobody seems to carry replacement inverters for that exact model. Does anyone know if inverters for other Gateway models will work (and if so, which ones)?
Thanks!
October 26th, 2009 at 4:33 pm
hi, i have an acer aspire 1520 laptop. i dont think there is anything wrong with the screen its like a light goes out, sometimes the light comes on at the windows screen for a few seconds but other times the light stays on, could you send me a reply to my email or this website on what you think please it has been really irritatin an it would be appreciated, thank you