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 (not even very dim image), 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.

Replacing inverter board on IBM ThinkPad T41

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.

Remove screw seals and screws

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.

Remove screw seals on both sides

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.

Lift up LCD bezel

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.

Removing LCD bezel

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.

Remove screw from the inverter

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.

Disconnect inverter cables

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.

Inverter FRU part number

Support this site.



Pages: « 70 69 68 [67] 66 65 64 63 62 61 601 » Show All

  1. 661
    Junho Says:

    I have a gateway mt3705 and the screen went dark. You can see it slightly with a flashlight. I tried replacing the inverter board but it did not fix it. Then i tried booting it with the inverter board unplugged and the same situation persisted (i saw a dark screen that i could see dimly with a flashlight. Does this mean my replacement inverter is faulty or could the problem lie elsewhere?

  2. 660
    Nevadaleigh Says:

    I have an emachine em350. Half the screen has gone white. and the image that I do have is what should be on the left side but it is on the right with what is suppose to be on the right missing.. I can scroll the screen around if on the net and see the whole thing.. and if I take a screen shot it shows the whole screen. But Its almost as if the screen has been shifted to the right, by half a screen. Help please.. they want 300 to put in a new screen which seems crazy when it is only 359 to buy a new one.

  3. 659
    cj2600 Says:

    @ Megan,

    Yes, the screen is almost completely black; I have to flash a light on it to barely see anything.

    I bought a new screen about two months ago. It shouldn’t have such a problem with a new screen, should it?

    Could be failed inverter board or backlight lamp. Cannot tell which one is failing without testing.

  4. 658
    Megan Says:

    I’ve tried to reboot my computer and all that jazz to fix my screen. Yes, the screen is almost completely black; I have to flash a light on it to barely see anything.

    I bought a new screen about two months ago. It shouldn’t have such a problem with a new screen, should it?

  5. 657
    Mortatita Says:

    Thank You Very Much!!!!!!

  6. 656
    bsmith Says:

    Hi, I have an HP G60 laptop. The problem is the backlight is not working. The LCD Panel works because you can faintly see the image. So first i figured the backlight bulb was no good. I bought and installed a new bulb and its didnt the same thing. So i figured I would try an inverter. No luck. last but not least I bought a new lcd panel and dont you know it, its still doing the same thing. Backlight is not turning on!!!! any ideas????????????

  7. 655
    Shaun Says:


    Well I contacted Acer directly about the problem. Because it’s out of warranty, they were of little help. Were more focused on me sending in a 5 year old laptop at the tune of $200+ to fix than assisting me.

    Through my research, I discovered that my problem was most likely a static electricity issue. I grounded my system at a usb port and the thing is working just as good as it ever has. Not sure why it’d develop the static issue all of a sudden, but I’m grateful it was a minor problem instead of a major one.

    Will it last? Who knows…I asked for a new laptop for Christmas anyways! lol

    Thanks for the assistance though.

  8. 654
    cj2600 Says:

    @ Shaun,
    Could be bad inverter or faulty backlight lamp. Cannot tell without testing the laptop.

  9. 653
    Shaun Says:

    I have an issue that I’m trying to diagnose. I’m hoping you all can help me.

    I have an Acer laptop and all of a sudden, my screen went dark. Never had a problem with this laptop before, so I guess it was due. Anyways, it works just fine when not connected to the A/C adapter. However, as soon as I plug in the A/C adapter, the screen goes dark. Does this mean it’s the inverter or a potentially worse problem?

    Any help would be appreciate. Thank you.

  10. 652
    cj2600 Says:

    @ ashriv,

    I have a hp dv 9000 laptop. The screen is no display but only comes back light on it.external display OK on the monitor. i had check display connector,display cable also it working fine.what is possibly the problem.

    Did you check connection between the video cable and motherboard? It’s located under the power button cover, close to the left hinge. Push on the video cable connector, make sure it’s seated correctly.

Pages: « 70 69 68 [67] 66 65 64 63 62 61 601 » Show All

Leave a Reply