Is it possible to repair LCD TV after a shock

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Unfunctional remote control

Before you start repairing the TV with your own hands, you should check whether the batteries from the remote control work. If they are dead, it is necessary to replace them.

Contacts under the buttons are dirty. To fix this problem you need to disassemble the remote control yourself and wipe the contacts, then put the remote control back together.

Damaged quartz transmitter. This may have happened if the remote control was dropped. Which means that it must simply be replaced, because in this situation the emitter is not repairable.

possible, repair, shock

The remote control has been exposed to liquid or has been completely immersed in water. To fix the problem you need to disassemble and dry the unit. If after that the remote control is not working, you need to replace it.

To replace a cracked display by yourself

If you decided to fix the problem yourself, use the following general recommendations. Read the installation manual beforehand. So, how to carry out a replacement:

  • Unplug the TV, remove all cables from the outside;
  • Place the device on a soft and flat surface;
  • unscrew the screws;
  • dismantle the frame on the damaged screen;
  • Remove the cables and wires from the inside, remove the screen
  • Assemble the new panel and make the connection of cables and wires. Turn on the power.

As you can see, doing everything with your own hands is not difficult. The main thing is that changing the screen does not cost you more than buying a new plasma.

Is it possible to repair LCD TV after a shock

The main component of such a screen is the matrix. The matrix contains just a huge number of particles that are filled with a mixture of neon and xenon. The perimeter of the matrix is framed by semiconductors. Electric current flows through the gas medium and creates a UV glow that causes the phosphors to glow. All this intricate process causes a cell to glow the color you want, and collectively tens of thousands of cells create the picture we see every day.

The entire device of the screen is located in a relatively small space between two planes that are usually made of special glass.

Important! Earlier models could boast of a glass thickness, which was only 3 millimeters. But progress along with manufacturers have made new models with a thickness of only 2 millimeters. Such innovations significantly reduced the weight of the device, but made it even more fragile, which leads to fraught consequences.

Read in another article for more details about the different malfunctions of televisions.

Can a cracked LCD TV screen be repaired?? Let’s talk about this.

Do you need to replace the matrix??

There is no and will never be a simple answer to this question. The bottom line is that each situation requires an individual solution. We can only tell you the basic principles and help you make your decision. So, if you have broken the TV, the first thing you need to pay attention to is the firm of the device, the cost and the extent of the damage.

If you bought your TV a long time ago, the manufacturer might no longer produce a matrix for your model. In that case, you will either have to buy new equipment or look for the necessary part in repair centers.

Important! For example, the well known Japanese company Panasonic stopped making plasma screens, and consequently. and matrixes.

It is worth trying to repair expensive TVs with a large set of features, because in this way you can save more than half of the cost.

Also it’s worth mentioning that sometimes the damage is not that extensive, so you can try to reconfigure the matrix instead of replacing it. If as a result of the impact the gas did not come out of the matrix, but only incomprehensible vertical and horizontal stripes were formed on the screen, the situation can be corrected. To do this, take your broken TV to a service center.

Important! A great advantage is that the cost of readjustment is not so high.

WATCH THIS VIDEO BEFORE THROWING OUT YOUR BROKEN FLAT SCREEN TV!!!

  • Old TV sets contain hazardous waste and substances that have a negative impact on the environment.
  • A modern model of broken TV can be scrapped for parts.
  • You can surrender your TV at Eldorado and buy a new one.
  • In a pinch, you can take your TV to a collection point.

Is it possible to repair a cracked TV screen (matrix) or is it just an expensive replacement? Unfortunately screen repair is not possible. The only option to restore the functionality of the TV is to replace the panel. Conclusion: Matrix repair is not possible, unfortunately there is only a costly replacement.

Plasma screen. what is it?

Let’s deal with what a plasma screen is and how it projects an image? The matrix is the basis of such TV and contains a huge number of cells, inside which is a mixture of xenon and neon. These cells are covered with phosphors. Also, there are special conductors around the perimeter, which contribute to the formation of ultraviolet glow when passing through a gas environment. This is what causes the cells to light up and glow in a given color. As a result, we can observe a holistic image.

Such a complex mechanism is between two, often glass, planes. But if before the thickness was 3 mm, today, in order to facilitate and slightly reduce the technique, manufacturers have made thinner planes, namely 2 mm.

Important! It’s true, as expected, it weighs less, but its mechanical sensitivity and fragility have increased many times over.

What is a plasma TV screen??

The main component of such a screen is a matrix. The matrix contains just a huge number of particles that are filled with a mixture of neon and xenon. The perimeter of the matrix is framed by semiconductors. Electric current passes through a gas medium and creates the UV-light that causes the phosphors to glow. All this tricky process leads to a cell glowing in the right color, and together tens of thousands of cells form the picture that we see every day.

The entire device of the screen is located in a relatively small space between two planes, which are usually made of special glass.

Important! Earlier models could boast a glass thickness of only 3 millimeters. But progress along with manufacturers have made new models with a thickness of only 2 millimeters. These innovations have noticeably reduced the weight of the device, but have made it even more fragile, which leads to fraught consequences.

possible, repair, shock

Read another article for more details about different TV malfunctions.

Is it possible to fix the broken screen of the LCD TV, if it is cracked? Let’s talk about this.

Causes of screen breakage

Is it possible to repair the TV, if the screen is broken or there is a crack? Let’s look at a few reasons for the problem:

  • Your TV has been dropped, hit with a heavy object, poured liquid on it or caused other mechanical damage;
  • Broken chips, which are responsible for the functionality of liquid crystals;
  • Pixel burnout has occurred, which is not due to mechanical causes;
  • The backlight is broken.

If it’s just a broken backlight there is hope that the LCD screen can be repaired safely. Especially if it is an outdated model with halogen bulbs, which are easy to change. But if LED-backlight technology is used (LED type), the repair is possible, based on the company. manufacturer. For example, many make models that have built-in LEDs, which are in loops that are not to be mounted. In this case, the situation can not be fixed.

LCD TV repair.How it works

Greetings to those involved in repair and just interested.Here we have mostly one cell phone yes videocards with laptops, let’s dilute it with LCD TV repair.In this post you will learn how to repair the TV with your own hands. Without registration and SMS, how your TV is built inside, how you can be cheated in the service center. And a little dip into the world of school physics with formulas and blackjack.So, drama according to the classics: The sound is there, the remote control responds, but there is no picture. precisely, it is there just you do not see, well, almost do not see, if you look closely or shine a flashlight on the screen at an angle, the picture is still visible.Experienced already guessed, the backlight does not work. The LG-42LB551V TV model, it has LED backlight, i.e. led, and despite the fact that amoled captures the market, TV sets with led backlighting are the most common, as well as still there are devices with backlight on ccfl lamps, produced at the beginning of zero. In this TV. The screen diagonal 42 inches is set 8 slats of 4 LEDs each, a total of 32 pcs, a failure of even one will lead to the inoperability of the entire backlighting system. But how do you know if the diodes are burned out or the problem is in the driver control board? Usually, when you turn on the TV on the backlight connector for a moment there is voltage. from about 170 to 280 volts, then it goes down. Sometimes up to 40 volts. Sometimes less, all this is relative and depends on the model of TV, but a stirring of the connector indirectly indicates that the driver is okay, the driver defect can only speak of a complete lack of voltage, otherwise the. Without loading the driver, it is impossible to make unambiguous conclusions. From experience, in ninety percent of cases the diodes are burned out. In addition, in this unit that something rattled and rolled over inside, plus the owner said that before the breakdown were white spots on the screen, which clearly indicated that the lens has fallen off the LEDs, which means that the diodes are strongly heated. To get to the diodes you need to disassemble the matrix. And here we have two of the biggest problems. First, the matrix, it is very fragile and the most expensive part of the TV, if damaged, that’s it. The TV can be thrown out. Second. Cables connecting t-con and matrix, if you damage them at the junction with the matrix glass then the repair is virtually no longer cost-effective. Removing the decorative front bezel. Remove or unscrew t-con, bend it towards the matrix and glue it to it like on the photo.

Now you need to remove the matrix, I use for this suction cups for removing the screens of cell phones. You can do it without, but it’s much more comfortable.Remove the matrix very carefully, it should be easy to remove, if it is not pulling, see what is holding it. remove the matrix and put it on a soft surface, in general, be very gentle with it. Next is the second frame where the matrix was, remove it. Underneath is a sandwich of diffusers. a lot of film and plastic.

Put on our gloves and gently, without taking it apart. lift the entire sandwich, try as much as possible to keep them clean and beautiful as they were after removing the matrix, any scratches. Dirt and smears on these films will be visible on the screen later on. If you leave fingerprints or dirt on the screen, you can wipe them off with isopropyl alcohol, it has been tested and proven to leave no traces. If you see stripes or spots on the screen after repair that are not round, it means that you have damaged the film. Then we remove the plastic stops that keep the sandwich and the matrix from sagging. Now remove the paper backing with slots for diodes.

And so we finally got to the boards.

They can be glued to the pallet or they can be screwed on. Now you can test them. In my case, one line of two bars, eight diodes, lit up with about twenty-four volts. The length of the strips and the number of diodes on them depends on the TV diagonal. Find the problem bars, then check the diodes in the bars. There are checkpoints on the slats. In my case it was possible to check only pairs, the pair lit up with about four volts. It is possible to check each diode by removing the protective layer from the tracks.Here we found the burned diodes. And what to do? There are several ways to do this. Replace all strips with new ones. Replace all the LEDs on the slats. Replace only the burned diodes. The most correct but the most expensive option is to replace all the bars on the new. Only in this case, we can seriously talk about warranty and quality. Diodes are correct. The diodes are well soldered and the lenses are well glued. The second option is also not bad, but it depends on the experience of the master. It is necessary to peel off the lens, quality selection and solder the diodes and quality glue lenses, otherwise there may be lights and other problems. Well, the third option, replace only burned diodes. worst but also the cheapest, and therefore the mass. First, the other diodes also degraded and do not know when they fail, a serious guarantee can no longer be. Secondly diodes can and most likely will vary in the spectrum of luminescence, hence the shines and may even be greenish picture. Third. To give at least some assurance, the master will significantly reduce the current (limit the brightness) forty percent or even more, such a restriction is visible to the naked eye. All this creates the ground for cheating the owner. You may be told to replace the strips with new ones but only the burnt-out diodes will be replaced. So you’ve decided what to do, repaired or replaced the strips. Reassemble in reverse order. Assembled. You think the repair is over? No. Talk about a worldwide conspiracy. You don’t believe me? But they are. In this overproduction crisis the manufacturer wants you to replace your TV about once every three years, but preferably more often. It is for this purpose that all manufacturers overestimate the backlight current. They set the voltage of diodes at the maximum permissible level, thus reducing the service life.Plus, it’s the economy, the brightness, we want more. Diodes are cheaper.All of this leads to a rapid failure of the backlight. And for this reason I always limit the maximum current of backlighting when repairing. On all TVs this limitation looks about the same, you need to modify the power supply by removing a couple (or one) resistors from the current feedback circuit of the backlight driver. This model runs on a BD9486F driver. Let’s look at the typical connection from the datasheet.

The maximum backlight current is set by the resistor Fs.Here’s how it works. The controller calculates the current using the formula Rs=#x2153; adim/Iled. Adim is the signal which controls the brightness of the backlight when you turn the brightness up or down in the menu. It can be different sizes but since we are limiting the maximum brightness let’s assume that its maximum value is 2v. Iled is the maximum backlight current we want to set, let’s assume it’s 200mA or 0.2A. The formula is Rs=#x2153;2/0.2=3.33 Ohm. Let’s lower it even more, to 100 mA. Rs=#x2153;2/0.1=6.66 Ohm. So if we want to decrease the maximal current we need to increase the value of Rs. Resistor Rs physically. As a rule, it is a group of resistors connected in parallel-serial, sometimes just in parallel. In this model it is a group of resistors R811-R818, here it is in the schematic and on the photo.

If you want to increase the resistance of a group of parallel connected resistors, you have to remove one of them, in this case break one of the circuits, I remove the resistor R811, just shift it. Now let’s see how the current has changed. Here are the readings before removing the resistor.

91.5 mA, this is not the maximum current, this is the current in no signal mode, in this mode, the TV itself dims the brightness, but this is not important now.Here are the readings after removing

68.6 mA, you have to understand that we have not lowered it by about 20 mA but by about 24%.

A reduction of 24% is almost invisible to the eye, but will greatly extend the life of the diodes.So that’s it. hope it was interesting.