lcd panel backlight not working price

The cost to repair a TV screen can be significantly more than the cost of purchasing a new TV. For this reason, replacing or repairing a broken TV screen is not considered feasible.

Most TV or electronics repair companies do not offer TV screen repair, and many warranties do not cover the service. For example, BestBuy"s 90-day warranty does not list broken TV screen repair as one of the problems they cover.

Unless you are trying to fix a TV from the ’80s or earlier, cracked TV screen repair is not feasible; the entire display panel must be replaced instead. The cost of a replacement TV display panel is often more than the cost of buying a new TV, and that’s before labor and other service costs.

The cost of TV screen replacement is generally the same as or more than the cost of buying a new TV. Therefore, replacing a broken or malfunctioning TV screen is not considered a viable option. If the TV is under the manufacturer’s warranty, the manufacturer may replace the entire unit.

TV manufacturers do keep replacement TV screen panels on hand to support products under warranty in case the screen malfunctions, due to manufacturer defect.

If you still want to replace a damaged or malfunctioning TV screen, your best option is to find a used replacement panel or a broken TV of the same model on which the screen is still functional. You might find one on eBay, and you can hire a technician to change out the panel.

Whether your TV is LCD, LED, plasma screen, or 4K (Ultra HD), the cost to fix common problems ranges from $60 to $350, depending on the repair type and the TV brand.

The function of an inverter board in a TV is to power the backlight of the screen. The inverter board requires a few hundred volts of power. If the inverter board goes bad, it causes the TV to power on with sound but no picture.

If an older model LCD TV or projection TV powers on and has sound but no picture, this may be due to lamp burnout, which is both common and expected. In this case, replacing the bulb will fix the problem. An experienced technician should be able to replace the bulb quickly and easily.

TV backlight repair costs $100 to $120, including replacement parts and labor, at a repair shop. In-house repair costs are more due to trip fees. The price of backlight replacement parts averages around $2.50for each LED and between $20 and $25 for each CCFL strip.

A new inverter may be needed to power the LEDs, costing $7 to $75before labor, or an average of $40. In some cases, a repair shop can convert a CCFL backlight to LED without installing a new inverter.

Backlight failure in a TV may also be due to failure of the power inverter that supplies power to the backlight. In rare cases, both the inverter and the lighting components fail.

It is not possible to fix a TV capacitor when it fails; it needs replacing. If your TV stops working while you are using it and you notice a smell similar to ammonia or bleach, this is a sign that a capacitor has blown. However, some capacitors do not make any noticeable smell when they blow.

Flat screen replacement glass is not available. The only option for flat-screen TV glass repair is to try optical glass glue, which costs $1.70 for a 5-ml. tube. This may be an option for TV glass repair if the crack is only a few inches or less. TV panels are built as one unit at the factory, with the glass adhered to the display panel.

LCD flat-panel repair is not considered cost-effective. If the glass is cracked or the display is physically damaged, it is cheaper to replace the entire TV than to repair or replace the display panel.

Estimating TV repairs costs by brand is not something TV repair shops offer, however, there are general prices by type. When looking for specific repair costs for your TV, you’ll find them in the common repairs price list above. Pricing applies to brands such as Samsung, LG, Sanyo, TCL, Insignia, HiSense, Sony, Toshiba, Pioneer, and Vizio.

The cost of flat-screen TV repair ranges from $40 to $350. You cannot fix a broken screen, but the price of a new flat-panel TV starts from around $250 for a 1080-mp (non-4K) LED TV from LG to as much as $15,000 for an 85-inch 8K LED TV from Samsung. A TV referred to as a “flat TV” or “flat-screen” TV might be any of the following:LCD TV

An LED TV is just an LCD TV that uses LED backlighting, which all newer models do (older models use CCFL backlighting). The cost to replace one LED backlighting strip ranges from $100 to $125, including parts and labor.

The cost to replace the motherboard, inverter, or LED"s in a 4K TV ranges from $100 to $275 or more, depending on the brand and model. The cost for screen repair for a 4K TV is irrelevant because it cannot be fixed or replaced at a cost that is lower than the cost of a new 4K TV.

Digital light processing (DLP) TVs are also known as projection TVs. DLP big screens have not been made since 2012, and DLP TV repair is usually not worth the cost except for a lamp burnout, in which the bulb can be replaced. The cost to replace bulbs ranges from $60 to $120.

With modern TVs, repair entails component replacement or replacement of capacitors, for which high levels of certification are not necessary. Generally, TV repair shops will let you know if their employees have certification.

If the TV powers on but you do not see a signal from your cable connection, satellite dish, or DVD player,First, check that the connecting cable is securely in the socket on both ends. If that doesn’t work, try substituting another data cable if you have one, or test it with a replacement cable.A data cable $4 to $15

TV Does Not Power OnPlug- If the TV is not powering on and no status LEDs are lighting up, start by plugging the TV into a different outlet. If the TV is too challenging to move, you can run an extension cord from another nearby outlet.

Circuit breaker- Check the circuit breaker for the power outlet that the TV plugs into. You can check the breakers by opening the door to your breaker panel and looking for circuit breakers that are in the OFF position.

Power cable- Check the power cable. If it is a removable cable, you can test it by substituting a power cable from another piece of equipment in your home, or you can buy a replacement cable for this test. The cost for a replacement TV power cable ranges from $2.50 to $10.

Remote control- If the TV is not powering on with the remote control, you should try replacing the batteries. For remote controls with a status LED light, there could be enough power to light the LED but not enough power to send a signal to your TV.

There are many reasons that a TV may power on but have no picture.Backlighting burned out -In modern LCD TVs, the backlighting may be burned out. A technician can replace LEDs or CCFL backlighting strips.

Inverter is bad -It is possible that the inverter, which powers the backlights, has gone bad and needs to be replaced. It’s also possible that one or more capacitors on the inverter have gone bad, in which case a technician may be able to replace capacitors more cheaply than replacing the entire inverter.

Lamp burnout -In a projection TV or older LCD TV, no picture may be caused by lamp burnout. In this case, a technician can replace the bulb quickly and easily.

The right parts- It can be complicated to determine which component of a TV is failing and causing the TV not to work correctly. If you buy a replacement part and perform the repair yourself, the TV may still not work, either because you replaced the wrong part, the part was old and not working properly to begin with, or you did not perform the work correctly. Buying multiple replacement parts can become costly.

The cost of repairing a TV could be as much as $500 if multiple repairs are needed. Consumer Reports recommends not to spend more than 50% of the cost of a new TV repairing the old one.

Not included in these prices from Best Buy are 1080p screens, which range from $250 to $280 for 43-inch TVs from brands like Samsung, Sony, and LG. On the upper end, Sony and Samsung both have 95-inch 8K OLED TVs for $70,000.

In most cases, a flat-screen TV can be fixed. The exception is a physically damaged display panel or screen.  Most other issues including failing speakers, backlights, or power supply. Burned out fuses and damaged input ports can also be repaired.

If the screen is not physically damaged but is not showing a picture or is displaying “snow’” or vertical or horizontal lines, a technician can repair the TV by replacing failed components. If the screen is physically damaged, it cannot be repaired.

You cannot replace a broken flat-screen display. New TVs costs anywhere from $249 for a 1080P (non 4K) LED TV from LG to as much as $14,999 for an 85” 8K LED TV from Samsung.

We manufacture and stock backlight assemblies for many NEC LCD panels. We produce premium quality replacements to extend the life of your flat panel screen devices.  If you do not see your panel model listed here, please contact us to learn about our cost effective design and manufacturing process.  Simply mail us a sample of the backlight you are looking to replace, and we can recreate and supply you with what you need to meet you needs.

Here are some simple instructions on how to replace a burnt out LCD backlight with a new working one to bring your LCD back to life.  Inevitably, every LCD eventually goes dark, but the process to bring it back to working order is not very hard.  As long as you are careful, it can be done successfully and without too much drama. Generally this is a very cheap repair, usually only around $10-20.

This instructable will be performed on a laptop LCD from an old Zenith Data Systems computer.  I tried to make this instructable pretty basic and not extremely detailed because every LCD screen is different. Your LCD will be different from mine (how its held together, the number of CCFL"s, etc) but the concepts will remain the same.  Feel free to send me any questions you might have, and I"ll try to help you out.

To get the the LCD screen and the backlight inside, you must first disassemble the LCD housing; this is different depending on whether it is an external monitor, or built into a laptop.  But first before disassembling the housing, DISCONNECT THE POWER!

EXTERNAL LCD MONITOR:Usually to get inside of an external monitor, you will have to simply take out all the screws on the back of the display and pull it apart.  Pretty simple.

LAPTOP LCD (Shown): This can be a little more frustrating at times, but not impossible.  First open up the laptop and locate all of the screws (sometimes these can be hiding under rubber feet).  After removing the screws, many times you will also need to use a flat head screwdriver to pry the housing open little by little.  Be gentle,, but don"t be afraid to use a little force.

In this step make sure that every element of the LCD you remove is kept in perfect order so you can easily reassemble it after replacing the lamp(s).  The LCD I am disassembling really didn"t require me to remove too much to get to the CCFL"s, but many times you will need to remove several layers of transparent sheets that are used to spread the light uniformly throughout the screen.

Just like before, locate and remove the screws holding the LCD assembly together.  Take the assembly apart including any transparent sheets in the way of the cold cathode tubes.

In this step you must be very gentle.  The lights contain mercury and are very fragile.  This step is not that difficult, just be patient.  Do not use any force when removing the CCFL or it will break (I speak from experience).  I would suggest that you loosen the wires from the LCD first and then gently remove the CCFL.

After putting your LCD back together, reattach the inverter and any other cables that may have been connected to the display.  Next, before putting the housing back together completely, test out your display to make sure everything is in correct working order.

NOTE: Be VERY careful with the exposed connections and cables, ESPECIALLY the Inverter. Touching the wrong part could not only hurt you, but damage your display.  Yet again, I speak from experience.

Ok so here is the deal. My screen was working well. Then a small spider showed up on it every day (on the glass, not under)... a tiny jumping spider, and I got attached to the little guy cause it was chasing my mouse pointer! I thought that was sweet, even if it would sometimes leap and attack it :D... which makes me think maybe the death of my monitor is related. It"s a Philips BDM4065uc, 4k. I LOVED that monitor. For 10 days the spider was around... every day. I once removed it and put it down at the other side of the room, next day it was back on my screen.

One day the top 1/3 of my backlight was down 50% in luminosity... but the spider was gone. Never saw it again. 5 days later, the backlight zones flickered, and 3 minutes later it was dead. My theory is that the spider went in, and something unfortunate happened. So mind you the spider was cute but not 680$ cute :). Oh well.

So I connected my monitor and a chrome TV and shone a flash light on it, I can see the Reconnect Me font from my chrome TV plugged in. So the screen works, just don"t have a backlight.

In your opinion, what should I do to try and fix this? Can I buy a backlight? could it be a board? a bulb?... I"m no electrician but I build my own computers, repair them, repaired or upgraded cpu/gpu in laptops, so I"m thinking I should be able to fix this (skill wise).

I have an old samsung SGH-A77 ( https://www.att.com/support_static_files/manuals/Samsung_A777.pdf ), but it has received some water damage, and the backlight no longer works. Everything else appears to be in order, including the LCD itself, but the LCD and the backlight are pretty much one thing. Any idea on how to go about fixing this so that I don"t have to buy a new phone?0

I replaced the CCFL bulb on my HP DV6-1030US 16" screen laptop. I also replaced the inverter. The screen now turns on and lights up, but the brightness is not as bright as it should be. It is about 50% or less of it is supposed to be. I reset the PC by holding the power button for aprx 2 mins without power on or battery What could it be wrong? Please help0

If the LCD is on and running (still dark) but you can still see a faint image, then its either the inverter or bulb.  If you can"t see any faint image at all, or if weird things are going on in the screen (lines, craziness) then I would check to make sure all your connections are tight (especially on a laptop).

Note: If your MacBook Pro has any damage which impairs the service, that issue will need to be repaired first. In some cases, there may be a cost associated with the repair.

"The instructions were very helpful!! Very easy to follow and it did not take long. The screen is working great. And, shipping & delivery were very prompt. Thank you for making this easy!" - Karen

"Believe it or not. This is my second screen replacement. The first install took about 40 minutes. The second I had my son do (since he broke it) and he completed in 30 minutes. Great product! Great instructions. Easy as Pie!!!" - Anthony G.

"Yes, yes, and more yes! This review is a little lengthy but stay with me. The quality is great, the installation was easy (I watched the matching video on YouTube), the price was amazing and the tools were soooooo helpful! I"ll never use another website, or company. Thank you so much!"

"The instructions were very helpful!! Very easy to follow and it did not take long. The screen is working great. And, shipping & delivery were very prompt. Thank you for making this easy!" - Karen

"Believe it or not. This is my second screen replacement. The first install took about 40 minutes. The second I had my son do (since he broke it) and he completed in 30 minutes. Great product! Great instructions. Easy as Pie!!!" - Anthony G.

"Yes, yes, and more yes! This review is a little lengthy but stay with me. The quality is great, the installation was easy (I watched the matching video on YouTube), the price was amazing and the tools were soooooo helpful! I"ll never use another website, or company. Thank you so much!"

I have never dropped my laptop, nor had it gotten any water damage. The screen used to flicker black and back (the backlight that is) over a year ago and a simple restart or tilting it slightly usually fixed it.

Recently it completely stopped working and used an external monitor to do my work. One day I randomly decided to open it open and found that the display was working as per normal and I was careful to not tilt it at all and it worked.

However, the backlight would flicker whenever the laptop started getting hot and once I accidentally closed the lid and the backlight was gone again. The display works as I see it when I shine a light through the Apple logo.

I’m not sure if the issue is the backlight IC on the logic board or the display flex cable as the other posts I’ve seen seemed to give various answers.

While the cluster is apart for an LCD repair, it"s a great time to replace other problem components in the cluster. This is a bundle of parts that we use when a cluster comes into the batee.com shop.

This article is about backlights in liquid crystal displays. For the rear window of an automobile, see Car glass. For the lighting design practice, see Backlighting (lighting design). For other uses, see Backlight (disambiguation).

A backlight is a form of illumination used in liquid crystal displays (LCDs). As LCDs do not produce light by themselves—unlike, for example, cathode ray tube (CRT), plasma (PDP) or OLED displays—they need illumination (ambient light or a special light source) to produce a visible image. Backlights illuminate the LCD from the side or back of the display panel, unlike frontlights, which are placed in front of the LCD. Backlights are used in small displays to increase readability in low light conditions such as in wristwatches,smart phones, computer displays and LCD televisions to produce light in a manner similar to a CRT display. A review of some early backlighting schemes for LCDs is given in a report Engineering and Technology History by Peter J. Wild.

Simple types of LCDs such as in pocket calculators are built without an internal light source, requiring external light sources to convey the display image to the user. Most LCD screens, however, are built with an internal light source. Such screens consist of several layers. The backlight is usually the first layer from the back. Light valves then vary the amount of light reaching the eye, by blocking its passage in some way. Most use a fixed polarizing filter and a switching one, to block the undesired light.

An ELP gives off uniform light over its entire surface, but other backlights frequently employ a diffuser to provide even lighting from an uneven source.

Backlights come in many colors. Monochrome LCDs typically have yellow, green, blue, or white backlights, while color displays use white backlights that cover most of the color spectrum.

Colored LED backlighting is most commonly used in small, inexpensive LCD panels. White LED backlighting is becoming dominant. ELP backlighting is often used for larger displays or when even backlighting is important; it can also be either colored or white. An ELP must be driven by relatively highAC power, which is provided by an inverter circuit. CCFL backlights are used on larger displays such as computer monitors, and are typically white in color; these also require the use of an inverter and diffuser. Incandescent backlighting was used by early LCD panels to achieve high brightness, but the limited life and excess heat produced by incandescent bulbs were severe limitations. The heat generated by incandescent bulbs typically requires the bulbs to be mounted away from the display to prevent damage.

For several years (until about 2010), the preferred backlight for matrix-addressed large LCD panels such as in monitors and TVs was based on a cold-cathode fluorescent lamp (CCFL) by using two CCFLs at opposite edges of the LCD or by an array of CCFLs behind the LCD (see picture of an array with 18 CCFLs for a 40-inch LCD TV). Due to the disadvantages in comparison with LED illumination (higher voltage and power needed, thicker panel design, no high-speed switching, faster aging), LED backlighting is becoming more popular.

LED backlighting in color screens comes in two varieties: white LED backlights and RGB LED backlights.blue LED with broad spectrum yellow phosphor to result in the emission of white light. However, because the spectral curve peaks at yellow, it is a poor match to the transmission peaks of the red and green color filters of the LCD. This causes the red and green primaries to shift toward yellow, reducing the color gamut of the display.a red, a blue, and a green LED and can be controlled to produce different color temperatures of white. RGB LEDs for backlighting are found in high end color proofing displays such as the HP DreamColor LP2480zx monitor or selected HP EliteBook notebooks, as well as more recent consumer-grade displays such as Dell"s Studio series laptops which have an optional RGB LED display.

RGB LEDs can deliver an enormous color gamut to screens.additive color) the backlight can produce a color spectrum that closely matches the color filters in the LCD pixels themselves. In this way, the filter passband can be narrowed so that each color component lets only a very narrow band of spectrum through the LCD. This improves the efficiency of the display since less light is blocked when white is displayed. Also, the actual red, green, and blue points can be moved farther out so that the display is capable of reproducing more vivid colors.

A newNanosys, claims that the color output of the dots can be tuned precisely by controlling the size of the nanocrystals. Other companies pursuing this method are Nanoco Group PLC (UK), QD Vision, 3M a licensee of Nanosys and Avantama of Switzerland.Sony has adapted Quantum Dot technology from the US company QD Visionedge-lit LED backlight marketed under the term Triluminos in 2013. With a blue LED and optimized nanocrystals for green and red colors in front of it, the resulting combined white light allows for an equivalent or better color gamut than that emitted by a more expensive set of three RGB LEDs. At the Consumer Electronics Show 2015, Samsung Electronics, LG Electronics, the Chinese TCL Corporation and Sony showed QD-enhanced LED-backlighting of LCD TVs.

CCFL backlighting has also improved in this respect. Many LCD models, from cheap TN-displays to color proofing S-IPS or S-PVA panels, have wide gamut CCFLs representing more than 95% of the NTSC color specification.

There are several challenges with LED backlights. Uniformity is hard to achieve, especially as the LEDs age, with each LED aging at a different rate. Also, the use of three separate light sources for red, green, and blue means that the white point of the display can move as the LEDs age at different rates; white LEDs are also affected by this phenomenon, with changes of several hundred kelvins being recorded. White LEDs also suffer from blue shifts at higher temperatures varying from 3141K to 3222K for 10 °C to 80 °C respectively.Benq G2420HDB consumer display has a 49W consumption compared to the 24W of the LED version of the same display (G2420HDBL).

To overcome the aforementioned challenges with RGB and white LED backlights an "advanced remote phosphor" cockpit displays,Air Traffic Control displays and medical displays. This technology uses blue pump LEDs in combination with a sheet on which phosphorous luminescent materials are printed for colour conversion. The principle is similar to Quantum Dots, but the phosphors applied are much more robust than the quantum dot nano-particles for applications that require long lifetime in more demanding operational conditions. Because the phosphor sheet is placed at a distance (remote) of the LED it experiences much less temperature stress than phosphors in white LEDs. As a result, the white point is less dependent on individual LEDs, and degrading of individual LEDs over lifetime, leading to a more homogenous backlight with improved colour consistency and lower lumen depreciation.

The use of LED backlights in notebook computers has been growing. Sony has used LED backlights in some of its higher-end slim VAIO notebooks since 2005, and Fujitsu introduced notebooks with LED backlights in 2006. In 2007, Asus, Dell, and Apple introduced LED backlights into some of their notebook models. As of 2008Lenovo has also announced LED-backlit notebooks. In October 2008, Apple announced that it would be using LED backlights for all of its notebooks and new 24-inch Apple Cinema Display, and one year later it introduced a new LED iMac, meaning all of Apple"s new computer screens are now LED. Almost every laptop with a 16:9 display introduced since September 2009 uses LED-backlit panels. This is also the case for most LCD television sets, which are marketed in some countries under the misleading name LED TV, although the image is still generated by an LCD panel.

Most LED backlights for LCDs are edge-lit, i.e. several LEDs are placed at the edges of a lightguide (Light guide plate, LGP), which distributes the light behind the LC panel. Advantages of this technique are the very thin flat-panel construction and low cost. A more expensive version is called full-array or direct LED and consists of many LEDs placed behind the LC panel (an array of LEDs), such that large panels can be evenly illuminated. This arrangement allows for local dimming to obtain darker black pixels depending on the image displayed.

For a non-ELP backlight to produce even lighting, which is critical for displays, the light is first passed through a lightguide (Light guide plate, LGP) - a specially designed layer of plastic that diffuses the light through a series of unevenly spaced bumps. The density of bumps increases further away from the light source according to a diffusion equation. The diffused light then travels to either side of the diffuser; the front faces the actual LCD panel, the back has a reflector to guide otherwise wasted light back toward the LCD panel. The reflector is sometimes made of aluminum foil or a simple white-pigmented surface.

The LCD backlight systems are made highly efficient by applying optical films such as prismatic structure to gain the light into the desired viewer directions and reflective polarizing films that recycle the polarized light that was formerly absorbed by the first polarizer of the LCD (invented by Philips researchers Adrianus de Vaan and Paulus Schaareman),

The evolution of energy standards and the increasing public expectations regarding power consumption have made it necessary for backlight systems to manage their power. As for other consumer electronics products (e.g., fridges or light bulbs), energy consumption categories are enforced for television sets.

The Evolution of LED Backlights; Adam Simmons; PCM PC monitors, Monitor articles, 12 November 2017; "The Evolution of LED Backlights | PC Monitors". Archived from the original on 1 December 2017. Retrieved 27 November 2017.

Dimming options for LCD brightness; J. Moronski; Electronicproducts.com; 3 Januari 2004; "Dimming options for LCD brightness control". March 2004. Archived from the original on 28 July 2017. Retrieved 20 November 2017.

LCD Television Power Draw Trends from 2003 to 2015; B. Urban and K. Roth; Fraunhofer USA Center for Sustainable Energy Systems; Final Report to the Consumer Technology Association; May 2017; "Archived copy" (PDF). Archived from the original (PDF) on 1 August 2017. Retrieved 20 November 2017.link)

Controlling Power Consumption for Displays With Backlight Dimming; Claire Mantel et al; Journal of Display Technology; Volume: 9, Issue: 12, Dec. 2013; Mantel, Claire; Burini, Nino; Nadernejad, Ehsan; Korhonen, Jari; Forchhammer, Soren; Pedersen, Jesper Meldgaard (2013). "Controlling Power Consumption for Displays with Backlight Dimming". Journal of Display Technology. 9 (12): 933–941. Bibcode:2013JDisT...9..933M. doi:10.1109/JDT.2013.2260131. S2CID 24082090.

If your laptop turns on but nothing shows on the screen, there’s a good chance the backlight is out.  The backlight in a laptop is the small CCFL bulb that illuminates the screen, usually from the bottom of the screen.  The light then bounces off of different plastic sheets, passes through the actual LCD pixels, and displays an image.  If this bulb goes out, or if one of it’s critical components go out, the laptop screen dims and it’s extremely difficult to see anything on the screen.

The best way to check is to turn on the computer and let it boot.  A tell-tale sign that it’s the backlight is if the computer boots normally – you hear the log on sound, for example – but nothing shows on screen.  Next, grab a flashlight and aim the flashlight at a sharp downward angle on the LCD.  If you can make out some colors or see your desktop, then you know the backlight isn’t working.  This is one simple test to see if this is the problem you are having.

The above symptoms are signs that there is something wrong with the backlight or other components. The backlight might not be getting enough power or may have a loose connection.

Getting this problem fixed really comes down to a good diagnosis.  Where someone might think it’s the LCD or the bulb itself that is bad, sometimes it is the LCD inverter that is the problem.  The inverter is a small device that transforms the low voltage of the laptop into a higher voltage – enough to turn on the backlight.  In many cases, both the inverter and the backlight are out at the same time.  It takes knowledge and experience to find out which part needs to be replaced.

If you have any questions about an LCD backlight repair, or computer repair in general, please give us a call to speak with one of our expert technicians!

Ever had your TV showing nothing but a black screen even if the audio was working? Unfortunately, that’s a common issue with low/middle-end LCD/LED TVs these days… Even more frustrating, this issue often comes from a rather tiny and cheap component that can be easily replaced. Most common issues are:

The first step into repair is to find the root cause of the issue. As backlight failure is a very common issue, this is the first thing to test. To do so, the easiest way is to power on your screen, put a flashlight very close to it and check if you can see the image through. The image would be very dark, like turning the brightness of the screen very very low.

That implies disassembling the TV to access the backlight which is between the LCD screen in the front and the boards in the rear. In my case, with a Samsung F5000, I had to process as follows:

First we have to remove the back housing to reveal the boards (from left to right: main board, T-CON, power supply) and disconnect the LCD panel from the T-CON board.

Note: Older TVs have neon tubes for backlight, which is thicker and less exposed to this kind of failure. LED backlight is the most common thing these days, but do not mistake an LED TV with an OLED TV. The first one is a classic LCD panel with a LED backlight, whereas the second is an OLED panel that doesn’t need any backlight as it is integrated in each pixels (making the spare parts much more expensive by the way).

As we can see, the backlight system is made of 5 LED strips. First thing to do is look for burnt LEDs. Most LED backlight systems have strips set in series, meaning that if one of the them fails, all the system goes dark…

One LED like those ones typically needs between 2.5-3.6v input voltage to light up. By looking up this model online, I found out that the ones used on those strips need 3.6v; so as there are 9 LEDs per strip: 3.6 x 9 = 32.4v input voltage required to light a single strip. That’s the maximum voltage we do NOT want to exceed, otherwise LEDs could be damaged during testing.

So, I took 3 9v batteries that were laying in a drawer, put them in series to make a virtual 27v battery (3 x 9v). It’s less then the optimal 32.4v required but not that much lower, it might be able to light the strip a bit so we can identify which is not working. Here is a look at the set-up:

Now we simply have to test each strips individually to see if they light up or not. For each that doesn’t completly, it will mean it has at least one defective LED.

After repeating this operation on all strips, I found only 1 defective LED, the same we thought looked burnt when we first had a look at the backlight (3rd strip from the top, 6th LED from the left). For a better understanding at what a burnt LED looks like here are 2 pictures of a burnt one and an OK one. Mind the roasted color compared to the regular one.

For starters I’ll go with the third one, just to make sure there is no other issues with the TV, but afterwards it’s better to replace the LED with a new one, otherwise you might notice a darker spot on the image.

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 wh