lcd panel backlight not working factory

Typically we see a lot of sets with some sort of backlight problem - this is mostly because people and manufacturers like to run the sets with the backlight at 100%. Unfortunately with LED backlit sets this causes LEDs to fail, often just outside of the warranty period. Below we list the common faults and list the best ways to fix them.

If you have some dark or black spots on your LCD screen, then it"s typically a sign that one or more of the LEDs on the backlight strips has gone bad. In the case of edge lit LCDs you will see that an entire line on your screen appears to be darker than the rest.

If you can not find the replacement strips you need on https://www.shopjimmy.com or are based outside the USA, we would recommend https://www.aliexpress.com/ as another great place to be able to find new and reconditioned LED strips.

If you are proficient with desoldering and re-soldering of surface-mounted electronic components / have a hot air rework station then you can buy the individual leds and swap out just the damaged ones on the strip, although we would not recommend this due to the amount of effort and the possibility of the replacement LED having a slightly different colour temperature or brightness.

If this is the case then you can take the set apart, and re-glue the lens to the LED. We will warn you however that this is a very delicate procedure to get the lens lined up exactly and so that the light output exactly matches all of the other LEDs. If you are not confident then we would recommend purchasing replacement strips and swapping the strips out entirely - new / replacement strips come with the lenses already glued / attached so you will not need to worry about alignment.

If you are willing to take your set apart then sometimes you will be able to diagnose these issues visually with very limited tools (this is not always the case).

Typically you will be looking for faulty / leaking capacitors on the LCD Power Board - although capacitors can sometimes fail and not show any visual signs. If you are able to confirm that the power board is operating correctly, then the next think to check would be the LED strips themselves. A quick visual check to look for burned or damaged LEDs may indicate where the problem is.

Warning: Disassembling your LCD set to get to the backlights is a complicated and delicate process, please be very careful when removing the LCD as it is very easy to crack it or damage the thin ribbon cables.

Remove all of the individual boards, taking great care not to snap any of the plastic connectors or thin ribbon cables (if you are struggling to unclip some cables, search for YouTube tutorials).

My TV recently turned off the backlight. Sound works and with the flashlight I can see the picture. I pulled out the power cord, after a few hours I tried again, worked fine, after about 5 minutes the backlight turned off again, the sound is fine and the flashlight test too. I noticed that if I let it be without power cord around 24 hours, the light will work for about 10 or 15 minutes before it turns off. When the light is working then the LED switch has 111.3-114.6 volts, but when it turns off, it is 144.6 volts. I also tried factory reset, not help.

Visually does not see the traces of burning on the power supply. And when the backlight is on, I don"t see dark spots on the screen, all the LEDs seem to work.

Liquid crystal displays (LCDs) are the most widely used display technology. Their applications cover TV, mobile phone, appliances, automotive, smart home, industrial meters, consumer electronics, POS, marine, aerospace, military etc. LCD screen display problem can occur for several reasons.

Effect of environmental conditions on the LCD assembly. Environmental conditions include both the effects of temperature and humidity, and cyclic loading.

Effect of manufacturing process. With the development of LCD for more than 40 years and the modern manufacturing equipment, this kind if defects are getting rear.

Common failures seen in LCDs are a decrease in screen contrast, non-functioning pixels or the whole display, and broken glass. Different kinds of LCD display problem need to have different kinds of fix methods or make the decision not worthwhile to repair.

Broken glassIf you accidently drop the LCD and you find it broken on the surface but the display still works. You might just break the touch panel; you can find a repair house or find a youtube video to replace the touch panel. If you find the display not showing, especially you find the fluid leaking out. You need to reply the whole display modules.

Dim LCD displayLCD can’t emit light itself. It uses backlight. Normally, the backlight is not fully driven, you can increase the LED backlight to make a dim LCD display brighter. But if you LCD display has been used for a long time, it is possible that the LED backlight has to be the end of life (not brightness enough) if you turn on 100% backlight brightness. In that case to fix LCD screen, you have to find a way to change the backlight. For some display, it is an easy job but it can be difficult for other displays depending on the manufacturing process.

Image sticking (Ghosting)Sometimes, you will find the previous image still appearing at the background even if you change to another image. It is also called burn in. This kind of failure doesn’t need to repair by professionals. You can simply shut off the display overnight, this kind of problem will go away. Please do remember that displaying a static image for a long time should be avoided.

LCD has white screen – If a LCD has a white screen which means the backlight is good. Simply check your signal input sources which are the most causes. It can also be caused by the display totally damaged by ESD or excess heat, shock which make the LCD controller broken or the connection failure which has to be repaired by professionals.

Blur ImagesAs the LCD images are made of RGB pixels, the screen shouldn’t be blur like old CRT displays. If you do see blur images, they might be caused by two reasons. 1) LCD has certain response time, if you are playing games or watch fast action movies, some old LCD displays can have image delays. 2) The surface of the LCD is made of a layer of plastic film with maximum hardness of 3H. If you clean the surface often or use the wrong detergent or solvent which cause the surface damage. To fix damage on LED screen it’s need to be changed with professionals.

If you have any questions about Orient Display displays and touch panels. Please feel free to contact: Sales Inquiries, Customer Service or Technical Support.

Hello… I have a dell latitude CPx laptop wtih the problem you described. The screen is still working but I can see only a very dull image. I do not find the lid close switch where you said it was. There is not any button close to the LCD screen, but the power button. Oh, this problem began when the laptop, into its briefcase,fell to the floor and slightly hit its back. Maybe is anything broken in it, like the backlight lamp or the video cable? I have not opened the laptop.

You cannot tell with part is failing the inverter board or the backlight lamp without testing the laptop with a known good backlight lamp (or inverter). I think you might have a dead backlight bulb because the laptop was dropped.

Hi, I think my back light inverter may be faulty. I’ve checked it with an external monitor and it’s OK. You can see the image on the laptop but it looks like every other vertical LED is not lit? ie if you look at the letter “S” it would look like a “$” I have a Compaq N800vp, product DJ125T. The question is, can I get a replacement back light or will I have to buy a whole laptop screen?

i’ve got a laptop diagnosed and they said i have a bad motherboard due to waterdamage. i want to take out the motherboard and put in a new one. however, rather than just put in the old outdated one, is there another motherboard you reccommend that would fit inside the laptop?? and how much would that run compared to putting an old but working replacement??

If you still can see the image on the laptop screen then the problem is not related to the inverter board or backlight lamp. When you have a dead inverter or backlight lamp, the whole LCD screen will be dark, not just some vertical lines.

I have a toshiba satellite M35X-S149 with what appears to be a bad LCD backlight. So i bought a “new” LCD screen to install. However, once I installed the screen, the same thing happened that the last screen was doing. The video would show up VERY faintly and the external video would work, but the backlight would not work. I tried switching inverter boards and nothing helped. I think I may have a grounding problem. I think i’m not putting the black wire with an “eye-hole” at the end in the right spot. Does anyone know where it goes? Please Help!

Last year the LCD light began flickering and I could hear a faint high-pitched noise. If I closed the monitor and re-opened to “wake” it back up, the light would work for a few minutes and then go out again. It eventually went out completely. Now, I can barely (barely!) see the screen (and as of a few minutes ago, for some reason I cannot get a screen at all). I have a desktop at home also, and tried to hook the monitor up to the laptop to no avail. I went through troubleshooting and cannot figure out why the laptop will not comply with the external monitor. I read through your posting and am a bit confused (I’m not good with the hardware aspect, so I’m clueless right now) so I’m hoping you have some insight…

So, you’ve replaced the LCD screen and the inverter board but still have no backlight? There might be a problem with the video cable. Also, it’s possible that you have something wrong with the motherboard but I doubt it because you have external video. I would try replacing the video cable next. Did you try reconnecting the video cable on the motherboard, just in case, to make sure it’s making a good contact with the motherboard?

It’s also possible but to find out you’ll have to disassemble the laptop and assemble “outside the laptop case”. Not sure if you want to go this route and I would do it only as a last resort.

Last year the LCD light began flickering and I could hear a faint high-pitched noise. If I closed the monitor and re-opened to “wake” it back up, the light would work for a few minutes and then go out again. It eventually went out completely.

This hight pitched noise and flickering screen could be caused by a faulty inverter board or failing backlight lamp. I would try replacing the inverter board first, you have a better chance to fix this issue. If it doesn’t help, you’ll have to replace the backlight (witch means replacing the LCD screen).

A few days ago I was troubleshooting a Dell Inspiron 600m with a similar problem. In my case the screen was making noise and it flickered as yours, but when the backlight was on, the white colors had reddish tone. I connected my test backlight lamp and it stopped flickering and the noise was gone. So in my case it was a faulty backlight lamp.

When your screen flickered, did you notice that white background had reddish tone? If it was normal white then most likely you have just a faulty inverter board. You’ll need more equipment (as spare backlight lamp or inverter board) to make troubleshooting more accurate.

I don’t like this one. So you had flickering screen/no backlight/faint image for a while and then it disappeared and now you have nothing? Could be a problem with the motherboard, video card, CPU or memory.

With the high pitched noise, especially if it’s coming from th elid, I’d suspect the inverter. You might check out the LCD troubleshooting flowchart I’m working on:

Before I order the inverter I would like to have one more question that might help if it is the lamp or the inverted. In the begining, before the screen is totaly black(not exactly black but with this shadow), sometimes suddently the light turned on until I switch off the laptop but next time again black. This hapenned for 3-4 times and then all black…This indicates if it is inverter problem or backlight lamp? Thank you…

It can be inverter or backlight lamp. You cannot tell until you test the laptop with a known good inverter or a known good backlight lamp. You’ll have to guess.

I would try replacing the inverter board first. There is a good chance to fix the problem and it’s way cheaper and easier then replacing the backlight bulb or the LCD screen.

After reading up on many websites, i figured i had inverter problem since my lcd was dim to the point where i couldnt see anything. I ordered the inverter from ebay and got it today. After replacing it, i noticed that the laptop works fine for few (2) seconds and then goes dim again. If i tap on the lcd close button, it again turns on for (2) seconds and then goes back dim.

Can I test a backlight bulb directly after buying without opening the whole screen?I mean can I connect it dirrectly to the inverter without the metal part for testing first and if it works then replace it?

I get the buzzing sound coming from the inverter and if I turn the brightness up the screen goes black and the buzzing stops. after it being on for awhile the left side of the lcd is slightly more dim than the right. external monitor works fine. Do you think its an inverter or bulb and if its the bulb where would i find one (inspiron 9400 – true bright screen) i found the inverter on ebay but can’t seem to see any bulbs maybe i’m not searching right. I want to know which it is before i shell out the money thanks

It’s very possible that there is connection issue between the vide cable and the LCD screen. I’ve seen this problem before. Reseating the video cable might fix the problem. You’ll have to take a look on the back side of the scree, that’s where this connector is located. Make sure the video cable is properly plugged into the connector on the screen.

I’ve been having problems with my backlight too. I have a Toshiba Satellite Pro M40 and the backlight acts strangely. Sometimes it will work fine, other times it will come on after a minute or two, and other times it will come on if I f**k around on the computer’s monitor settings. It has been doing this for about a year but I can always get it working in a few minutes before. But for the last few days it hasn’t turned on at all no matter what I do. I’ve known for quite some time that it was my screen itself because I sometimes have to use a flashlight to see to get to the monitor settings. I don’t plan on taking it apart but I’m grateful to posts like these that can help me pinpoint the problem to tell the repair shop.

I’m working on an Thinkpad A22m (2628-SSU) that was dropped. The LCD is displaying but only very, very faintly. I figured I could do an upper half replacement and ordered one from eBay. So far I have been unable to get the replacement to display anything. The damaged LCD panel is 1400×1050, while the replacement is 1024×768. Could that be the cause of my problems?

I have a toshiba satellie L25 S121. I dropped it and now the backlight isn’t working. I can barely see my desktop. Any help would be appreciated. Thanks.

2. Damaged backlight lamp (CCFL), in this case you’ll have to either replace the lamp (no easy) or replace the whole LCD screen (much easier but more expensive).

Yes, I purchased the whole LCD assembly. Lcd panel, inverter, cable, bezel, etc. I can’t get anything to display at all on the new assembly. I’ve tried changing several BIOS settings thinking that could be the problem, but still no joy!

BTW, what could be the problem with the old display? I am guessing since it was dropped that it is the bulb. The LCD panel is not cracked and still displays (although very darkly).

So back to the LCD assembly that I purchased that will not display anything, 1) it could be bad, 2) I could be doing something wrong… although I’m not sure what, or 3) it could be incompatible. Now that I think about it, it makes sense that the output from the video card needs to match the LCD panel. Will a 1024×768 panel work where a 1400×1050 once was? Thanks for the help.

The first weird behavior I noticed was the pinkish colors when my screen was just turned on and the colors were normal after a few seconds. I don’t remeber when was this behavior started, but I think it is at least for the last 2-3 months.

Disconnect the LCD screen on your laptop from the inverter board and plug the new screen instead. In this setup the video signal still goes to the old screen and you still should see a faint image on the old screen, but the inverter board will provide power for the backlight lamp inside the new screen. If the lamp inside the new screen is good, it should light up (I assume the inverter board is working fine).

Did you buy and swapped the whole display assembly or you bought all parts one by one? Did you try replacing parts one by one? First inverter, then LCD and finally the video cable.

Toshiba service replaces the LCD with 940 euros!!!!! Of course this is not an option, I better buy a new laptop. On ebay the price is much better, around 200 euros but then I am worrying if the screen will be ok after doing the long trip from USA or China to Greece.

My display failed on my A70 after disassembling due to the overheating issue. Laptop powers on, hd fires up, no beeps, just no display. Reseated inverter wires, ground and video on the board…still nothing. Took it all apart (again), reseated the CPU and heatsink….still nothing.

OK… I think I have a good little problem for someone to try to solve. My laptop backlight wont light up. Everything works and looks great when I send the video to an external monitor (my TV). I can also see the picture on the laptop monitor if I look closely and use a flashlight. I replace the inverter board… didnt fix it. I took the lcd apart and I have a new backlight as well as the old backlight resting comfortably outside the lcd panel so that I can see it clearly. Here is what I see. Please Help. When I turn the laptop on, the backlight flashes once real quick, and thats all I get. I don’t know if the inverter I put in there is just another bad inverter board or if this is some sort of power supply issue or something else. Please Help

The LCD panel on my IBM ThinkPad T60 (model #1953-D9U) got cracked, but with the exception of a small 2″ square area where the damage occurred (white screen), I could still use the laptop with the screen open.

However, now that I have tried to replace the screen with a new one, I cannot get the new screen or the old one to light up. I thought I may have damaged the inverter, so I bought a new one and installed it. However, I am still not getting power from the inverter to the new LCD (no backlight) and the images on my old screen are very faint…as if it was a bad inverter. (FYI – The external video still works perfectly.)

I have not tried to replace the LCD cable yet (perhaps I damaged it when removing the old one?), because I am trying to find out where the “closed lid” switch would be on this model. (My old T30 had a mechanical switch that could be depressed, but this one doesn’t.)

I thought I had a bad inverter so I bought one on ebay… guaranteed not to be DOA. It did not fix my problem. After thinking and scratching my head for a bit, I decided that the issue was still the inverter. I bought another one and this one fixed my problem. What is the point of this story? Well it is simply where did you get your inverter? and how can you be sure that this replacement part is in working condition? After all the one I bought was guaranteed to be NOT DOA but it was in fact DOA.

Let’s say you have the new LCD screen installed. Leave the data cable connected to the back of the screen but disconnect the cable witch goes to the inverter board and plug the old LCD screen instead. In this combination you still should see a very faint image on the new(installed) screen but the inverter board should light up the backlight inside the old screen. If there is no backlight, swap the inverter board and try again.

After that install the old screen back into the laptop. Connect the data cable into the slot on the back of the LCD, but plug the new screen into the inverter instead. In this combination you’ll get image on the old screen but the backlight will be on the new screen. If no backlight, try swapping inverters.

Also, you may try connecting LCD and inverter without mounting them inside the display panel case, maybe it’s grounding somewhere and will work outside the case.

If you still cannot get the backlight and your parts are supposedly good, apparently there is a problem either with the video cable or with the motherboard. Just in case check connection between the video cable and the motherboard located under the keyboard, maybe you accidentally pulled the cable.

If you cannot see the lid close switch, apparently it’s a magnetic one and located somewhere inside the laptop case. I don’t think this is your problem.

I am having trouble with my satellite m35x-s111 lcd display. I can see the whole image, but the lcd brightness is very low. I also noticed that brightness is higher in the right side of the display. How can i know if the trouble is in the inverter module or in the backlight lamp? The lamp can be easily replaced? Thank you.

Unfortunately, I cannot tell you witch one is causing the problem. You’ll have to test the laptop either with another working inverter or another working backlight lamp.

It’s not easy to replace the backlight lamp because it’s located inside the LCD screen. You’ll have to take apart the screen. You can easily damage the screen if you have on experience with fixing laptops.

myToshiba M70-215 has faint light, i had taken to repair, they tried invertor and couldnt repaired. Now they take to far away for repair and send computer for that reason. The laptop works fine w/ external monitor, and vision on original screen is very faint , can be seen on very light environment. So i dont think my screen went totally off. However, the repairment men from where my computer send gave us estimated repair demage and cost claiming that LCD screen went off and screen need to be replaced and sure that cost 250 USD. I am having hard time to belive ( since laptop is not older than 2.5 years just after waranty end!!) that and never dropped, that screen went out. Ithey just wanted to suck me i have strong belive right now it is backlight lamb and not invertor.

As an expert would you confir me that if screen went off i would never get any vision on screen right ( besides i used to have loss of light or brightnes while computer works few months aga, any time i turn off computer then light was comming on scree. The final and resisting light loss happened while i am using computer, the vision sudenly gone, and screen can be hardly seen with carefull look. So just give me some expert information before i decide replace my LCD screen. Do you think it need to replace LCD screen or light bulb. We tested inverter by bringing new inverter from Toshiba but didint work.

would that be reason hard to replace light bulb ofr Toshiba M70-215 screen, so they might be asking for whole LCD replacement ? Is it easy to replace light back bulb, and what is the aproximate cost on that lamb?. Is there any visiual show of that light bulb might be?

I found out that repairmen is trying to sell me whole LCS screen. It is only problem is backlight lamb and since they dont carry the lamb he wants to sell me whole LCD secren w/lamb..So iwas right on. Besides same attitue Toshibe center has, they want to sell whole LCD screen for about USD500 when i told only backlight need to replace as other repairment diagnosed at distance, Toshiba center is even unaware or pretending as unaware there is even backlight lamb…so kind of ridiculus bussines going on here. Now i am going to on my own, try to collect proper lamb and fix it w/ myself or fix w/TV repari man who would do things more chepaer…

If a known good inverter didn’t fix the problem and the image on LCD screen is still very faint, most likely you have a problem with the backlight lamp (CCFL) inside the LCD screen.

It’s not easy to replace the backlight lamp because you’ll have to take apart the LCD screen. Most repair centers will not replace the backlight lamp, they will swap the whole LCD screen.

I Don’t think my screen problem is related to an inverter or a backlight. When I fire up the computer my screen flickers and depending on how I move the screen up and down it gets better/worse. I have a 1.5″ area top to bottom on Left hand side which remains uneffected but the rest of the screen is distorted. I took it apart and when I tap the top back of the screen with my finger it replicates the problem. This area is near the cable and the Green circuit board.

I’ve got Toshiba M70 with a slightly different screen problem. Everything works fine on an external monitor but with the laptop screen, at first it appears the screen is dead. The screen remains black when booting up, but if you look closely, it is noticable that there is light behind the screen, I just wasn’t getting an image. I started poking around and found that if I squeezed the top left corner of the screen, I got a nice bright image and the computer was working fine, my thumb gets really tired while surfing though. It has to be some sort of connection problem, but I just can’t find it.

I am having LCD issues with a Dell Inspiron 6000 laptop. I have replaced the inverter initially, and tried replacing the bulb with no success. There is still a ghost image on the original screen, and the laptop works fine with an external monitor attached. I finally broke down and got an aftermarket LCD screen, which works but is very

my laptop Aspire acer 7620 bios setup was passworded by my younger brother, And he has forgoten d password and operating on d laptop as corrupted,and there is nothing i can do than to boot to the cmos setup and setup the boot option to load another operating system.and have tried all the master password that i know none of it solve the problem .now i dont know what to do either to go for a new laptop or i should try other site for help.please if anyone can solve my problem i promise to be his or her friend forever.i also i’m an engineer and i’m fed up with it.THANKS.MY LAPTOP IS A PHOENIX MAKER.

[…] First of all, take a closer look at the LCD screen. Look at the screen under bright light. It’s possible that the image is still on the screen but it’s very faint. If that’s the case, check out these tips for troubleshooting laptop with backlight failure. […]

My problem sounds very similar … when i press the Lid close switch and then release it, the light comes back and the screen is well lite but only for a few seconds. it doesnt seem to be the backlight since when it does lite up it looks as usuall.

2. If you still have the same problem, probably the backlight lamp is bad. If that’s the case, you’ll have to replace the LCD screen. It’s possible to replace the backlight lamp inside the screen but it’s not easy.

My Dell laptop went black today, after flickering just a bit for the last week or so. From everything I’ve read, I’m thinking it is the inverter since it works with external monitor and it actually lit up once when I brought it out of the screensaver mode. I talked to the Dell tech support and finally got the guy to tell me one of the tests to try. It sounds crazy, but he said if you turn it upside down and then power up, if the screen lights up you know it’s not the backlight, so it’s likely the inverter.

Well, I didn’t power down, but closed the lid so it went to standby. I turned it upside down and then opened it and voila! the screen looked normal. The one thing I still wonder about is something I read about a failing backlight causing the inverter to shut itself down. That scenario isn’t proven or disproven with my test. So I guess I’ll get a cheap inverter and see what happens.

I had the same issue with the backlinght very dim on the lcd screen on a dell laptop. So I replaced the inverter but it had the same issue, then I went ahead and replaced the entire lcd screen with inverter and backlight and still had the same issue, so I tried moving the motherboard to another laptop and still had the same issue so I just replaced the motherboard and that worked.

Unfortunately, replacing the inverter didn’t fix my problem. I’ve gotten a replacement backlight, but it doesn’t have connectors as it was advertised, so I have to solder it. Since the inverter I bought was refurbished, I wondered what are the odds I got a faulty one?

Since I now have 2 inverters and 2 backlights, I should be able to test different combinations, but I only have one set of wires so it’s more difficult…

My Hewlit and Packard laptop screen stays completely blank and iits like its trying to keep starting up.No movement on the hard disk light on the front.Tried to get ti to go into safe mode by pressing F8 but nothing.Any ideas.Had this problem recently but then after doing the same thing of continualy waht sound like it was turning off and on the screen loading sign came on with the black background.This time nothing comes on at all!!!!!!

I have a Satellite Pro A10 with dim screen, I have tested the backlight and that works fine, I bought another inverter but nothing changed although this could be faulty too. I would like to know can anyone tell me where the lid close switch on this laptop is please. So that I can check this problem before buying yet another inverter. Thankyou

Last night, shut the top for the evening and this morning opened it to find a very very very dark screen. The display never recovered. However, with a flashlight you can see that the computer is functioning just fine. Its too weird peering into your LCD with a flashlight and seeing the image ‘somewhere in there’.

Inverter board or back light? Plugged the video output into the TV and got my desktop just fine (but its not a HDTV so the quality was crap). Ok, there’s a screen in there – but its like looking into deeply smoked glass.

My Service Manual shows an inverter board and a display assembly in the exploded parts view of the unit – but no back light or bulb? Customer service online chat just told me I needed to replace the display assembly part … but yikes! that is the entire LCD screen kit and kaboodle! Huge price difference between CCFLs and display assemblies!!!

However, I do not know how to determine if I need to replace the inverter board (easier looking job for about $45)… OR, if I need to replace the CCFL bulb.

I had a power pin fault (had loose connection with board circuit) and managed to fixed by removing the board and rejoined with soldering iron. then it works ok but the lcd display became blinking and then turned into negative film like colour (like a film negative shading-no original colour), some times turn to normal then go blinking…. like over lightening or bright light is over the normal screen.

I have an HP ze 5700, the screen kept blinking and finally failed. I installed a new inverter board a few months ago and it still blinks white with the background still there. Do I have a backlight promlem and how much is a new one.? I’m not very good at this and I dont want to spend a lot of money unnecessarily. I’m just a retired person.

Impressive site! I’ve got an asus s5a 12.1″ laptop, and my backlight falls out when I tilt my screen to far backwards. First the light on the left side goes out, then if I continue to tilt, also the right light goes dark. Do you have any idea where to start..? Thanks!

– Reducing the backlight power ( fn + [left arrow] ) makes the backlight last longer, for an hour so far. The flashes, however, continue and some of them are brighter than the screen should be. (Ignore that, it lasted for over an hour now, flashes disappeared)

Could it be the lid switch? It’s a magnetic, not mechanical and I have no clue on how it works or whether it could cause the behaviour described above.

I’m having similar problems as described by the many replies herein. My screen initially went black about two months ago. I could still see the image if the light in the room was turned on, and connecting my laptop to the TV produced a perfect image. Opening and closing the lid would bring the picture back, but only for either a split second or, at most, two or three seconds. Then, about a week later, I opened the lid one morning and the picture stayed on for maybe four or five days! This cycle repeated itself for the next few weeks. (It should be noted that during the periods when the screen stayed on there would sometimes be a slight flickering effect.) So I ordered a new inverter. The website I ordered it from did not have the exact part number I needed, but it did offer an inverter that was compatible with the part number of the original. After replacing the original inverter with the one I purchased, the longest the screen lasted before going black was maybe 30 seconds, AND I heard a buzzing noise that I did not hear with the original inverter. So I put the original inverter back in and for whatever reason the screen didn’t black out once for a good three weeks. Well, for the past week the screen is going black again. Opening and closing the lid did very little until I figured out that if I pressed my finger once into the screen bezel directly over the invert and then closed and opened the lid, the screen would stay on for hours at a time (in some instances, a day or more!). However, there was a new wrinkle: manually adjusting the screen’s brightness directly affected when and how the screen would go black. Adjusting to the dimmest screen setting would eventually result in screen flickers that, after a few seconds, would lead to the screen going black. Adjusting to the brightest screen setting would result in normal image functioning. This lasted three days. Now the screen is going black again. Opening and closing the lid produces an image for a few seconds, except now the left half of the screen is very dark while the right half looks normal. And the kicker: When I switch the original inverter with the one I purchased online, the entire screen lights up like normal but will still go black after 2 – 10 seconds go by.

So does this sound like a backlight issues (I have dual lamps)? Does it sound like I should try finding an inverter with the same part number as the original even though the one I purchases should have been compatible? Is it possible the one I bough online is faulty? Any suggestions would be supremely appreciated!

Your problem sounds either like a bad inverter or bad backlight lamp. Unfortunately, the only way to find the culprit is testing the laptop with a KNOWN GOOD part.

I would try installing a new inverter with the same part number. If you still have the same problem with the screen, most likely it’s bad backlight lamp.

Great article! I tried an test inverter, no change, tried a test backlight. New inverter does nothing with new backlight. Old inverter causes backlight to blink briefly during startup then nothing. Anyone seen this before?

Thanks for setting up a help website. I was just wondering how you take the panel of where the backlight is. Im going to attempt to fix my laptop when i get home. cheers

I replaced the backlight with a one that I got on ebay. I was actually a cracked lcd display. and I took the entire frame which had the backlight in it and replaced mine with it. I did this so that I would not damage the backlight trying to get it out of one frame and put it to another. After all this the screen was still the same. So is it the inverter ? If the inverter was faulty would it have burned the backlight? If its the case the one I replaced may have been burned as well. Do I need to replace both and see?

Ive justt recently been having troubles with my Toshiba Satellite m50..i have the same problem as the rest with my backlight..but it ocassionaly goes but then goes out after a while..ive unplugged an replugged the inverter thinking it could be a bad connection…any other ideas?? help would be appreciated thanx

From this description it sounds that you have a problem either with the inverter board or backlight lamp. I cannot tell which one is causing the problem because both parts fail very similarly. The inverter would be my first guess.

I restarted it, and there was the light again, but it disappeared again and did this with the light disappearing in smaller intervals. Eventually the light was gone just after the BIOS sequence, and i stopped doing this when there were coming some strange noises and a not so nice smell from the laptop.

I just bought a Gateway MT6451 with a broken lcd. Ordered a new one, installed it and nothing. So I put the old one back in and that works. So I decide to test the inverter and backlight, both work. I then unlug the broken display backlight but leave the video cable hooked to the bad display, hook the new display’s backlight to the inverter. power up… backlight works…so while the laptop is on I unplug the broken lcd video cable and plug it into the new one…it worked. But only till I reboot. I did it like 6 time and it worked that way each time. Oh and the vga and svideo ports work also. Anyone know why its not turning my new lcd on?

Thank you. Before I had been wondering why my notebook screen looks a bit reddish on the sides when it’s running on battery. Now I know why, thanks to your article.

I have a HP Pavilion with a backlight problem, I first replaced the inverter and that didn’t work. Then a new display and again that didn’t work. Next the video/display cable which still didn’t help. Then the motherboard with no help. There is no visible lid close switch. Seems like one of these parts should have fixed it. I have had a dim display through all of this that can be seen using a flashlight. Any other ideas other that a new computer?

Did you try all possible part combination? For example, the old motherboard and old LCD with both new and old inverters, both motherboards with the old and new LCD/inverter, etc…

I had the same problem with my DEll Inspiron 6000. The monitor went totally dark. I was not sure if it was the inverter or the backlight. The monitor was bright for a couple of seconds when the DELL logo pops up, and then went dark. There was no reddish tone on the screen and so I guessed that it was the inverter (which is much easier to replace compared to the backlight). Replacing the inverter worked for me and it only cost 10 bucks.

i broke my screen on my aspire 3630 so i bought and fitted a new one,but i cant get the backlight to light.windows loads up as normal but without backlight.i have tried the lid switch and this appears to be working fine(windows goes to standby)

i have changed the inverter and tried the screen in another laptop and it works fine.so i tried to connect it to a external monitor but it only goes as far as windows xp is loading then,external monitor goes off (no signal),but the laptop screen loads up as normal without backlight!

Dell Latitude C800 LCD problem intermittent, no 100% indicative of back light or inverter failure so I am wondering if the LCD screen could be faulty? The machine will run well for days and then this will crop up again. I’ve run an external monitor successfully to rule out adapter problems.

The only sign of back light failure (after educating myself via this site) is infrequent and very brief screen flickering from full illumination to black out…nothing in between.

Your description of notebook backlight failure is exactly my problem. The screen is not completely black. I tried the first suggestion, but even a quick flick of the lid button, the notebook went into hybernation. When I started up notebook again the screen is fully lit. I tried closing down my notebook again, but on restart the same problem occurs each time, but when I depress the lid switch button and restart from hyberantion the screen is fine. Any idea what the problem is???

I am having trouble with my Toshiba laptop screen. It was very dark. I replaced the inverter & when I turned it back on it came on but then went dark again. I discovered that when I tapped the metal lid closed plate it would come back on. This worked for a few hours but now it is dark again & tapping does no good. Do I need to replace the lid closed plate, the backlight, screen, or is it possible I have damaged the new inverter by tapping on the plate too much?

My AC adapter has a short in it. The local shop tried a universal adapter with a couple of tips but nothing worked. If I I wiggle the cord on my original adapter, I can get enough power to max the battery at 100% within the usual amount of time. Two questions:

Ultimately, the computer works fine except the LCD screen. It works with an external monitor, and when the lid closes it hibernates so it is not a lid switch issue. The screen is dead black, no image at all so I am trying to narrow it down to power supply, inverter or backlight. It’s a 3-year old Toshiba Satellite A105.

The weird part is that the dim image shrink to 60% to the left. Other 40% is just blank image. I don’t have any invertor or CCFL lamp to test on. But I guess the whole lcd is the best way.

Hi tech guru…I was wondering if you can you help me figure out whats up with my dark screen. I can see everything but its just too dark… I have a dell inspiron 6000 and I accidently dropped it from my counter top. I have replaced the backlight and the inverter and still have a dark lit screen. My case looks exactly like your first picture on this page. I have also used an external monitor to test the video card and it works just fine. What can it be? Thanks in advanced!

Question about backlight testing – Should a good backlight have continuity across it’s terminals if it’s good? I was assuming yes, but all the backlights that I tested (1 out of 5 was good for sure) had no continuity when tested with an ohmmeter.

I just opened the laptop(dell inspiron 5150) to dust the fan and after closing it began to function but refused to display. I tried several times making sure that the video cable is okay but it still did not come up.

hi there i think i have a Philips 15NB57 series. i think my problem lies within the backlights hinge sensor as the screen its self works fine and i get a display through an external monitor. the backlight switches on for a split second during startup and also will do when inserting or removing the connection for the external monitor it will also come on when the lid is in a near closed position but only briefly again. is there anyway i can bypass the hinge sensor through the settings or is it something i’ll have to get repaired? (am using vista if that helps)

Thanks for the useful site. I have a laptop which half the screen is completely black (the bottom half). When I connect the laptop the external monitor, it is no problem to display to external display. SOmetimes when I open and close the lid, it works fine but after a while, the bottom half of the screen freezes (i can not move my mouse over it).. I opened the laptop and check all

My problem is a little different from others I’ve read. After turning on the unit and heating up for 10 minutes, I get a small semi-circular black spot that appears in the lower right hand corner of the screen. It appears as about the size of a thumb print. It will remain and after the unit runs for additional 10 minutes or so, the screen will start to “flicker” and become distorted. I have not just left it on to see if it will go totally black. After shutting off and cooling then restarting, the screen is clear until it warms up again. Would this be the inverter or a screen problem?

Have a Compaq Presario C500,when turn it on,screen stays on for about 15 seconds then turns off but there is very faint image…have not tried external monitor (next step),do you know how to get disassembly directions fot this laptop?

I have fujitsu siemens amilo v2010. The image on screen is very dimm. I tried good known backlight lamp, and it is not working. Replaced with new inverter, also no luck. Image is very dimm like backlight failure. Could it be video cable or bad motherboard?

thank you so much (in my tongue = terima kasih banyak) for your article this help prevent me from buying another inverter or backlight or even a new lcd screen