TV backlight repair

For many users, television has become an integral part of life. This device often serves as the primary source of information. and even if someone prefers to receive it on the Internet. The TV device is still used to watch movies or TV shows on the big screen. Often, TV breakdowns are very difficult to fix at home. This is primarily due to the technically complicated design of the device itself.

In the era of microcircuits, the complexity of repairs lies in the inability to replace most parts. That is why, faced with a breakdown of the device, users are forced to purchase a new one or carry a broken one to the service center. However, this article will describe how to fix a fairly common and complex malfunction in the form of a broken TV backlight.

Why the backlight breaks

On most TVs, the image begins to disappear only after several years of continuous operation. For budget models, the life without breakdowns may not even reach a year. Then, in order to continue watching movies on TV, repair is needed. True, replacing any part on an LED TV will cost a lot.

Most modern models provide images with LCD technology with LED backlight. To begin with, a few words should be told about the technology of liquid crystals. It is a feature of crystals changing their location under the influence of electric current. Due to the change in position, the light passing through them is refracted, which forms a different contrast of brightness. Then the filters create a color scheme that the user sees on the screen.

The most common reason for image loss on such TVs is a failure of the LED panel, which is a special LED. To troubleshoot with such a backlight, the user requires basic skills in electrical engineering and special knowledge.

REFERENCE! If he does not have the necessary skills, there is a risk only to aggravate the breakdown, which can make the cost and complexity of repairs many times higher.

Can I repair it myself

The first step for the user is to accurately diagnose the fault. If the image suddenly disappears on the screen, but the sound is fully reproduced, it is quite possible that the problem is in the backlight. In order to exclude other options, you should illuminate the screen with a directional light when the TV is working. With the presence of external light, an image should appear on the screen. If this does not happen, then the problem is different. If the picture was displayed on the display from the light of the flashlight, then the problem is precisely in the violation of the backlight.

LED backlight failure has two main reasons.

1. LED malfunction due to short circuit or open contacts. In this case, the entire circuit will be powered by the rated voltage, however, the diodes will not be activated due to their failure or violation of the integrity of the wiring.
2. Problems with backlight control. This problem is characterized by a lack of power to the lamps, which is why they do not burn.

After the problem is detected and diagnosed, the user has a choice: try to repair it himself or call the wizard, for repair work.

If the user has wide knowledge in the field of repair of this kind of equipment, he can try to fix the problem with his own hands. However, if he does not have the skills and knowledge, as well as special tools, it is better not to accept attempts to troubleshoot, but to use the services of more competent specialists.

How to adjust the backlight

First of all, you should start parsing the screen. To do this, unscrew the bolts on the perimeter of the housing. After removing the back cover, the user will see the main boards of the TV device. There are three of them:

1. BP - power supply. On it is the backlight driver.
2. Main board
3. Control board.

Next, an experienced user needs to dismantle the boards. During this process, it is very important to be careful and careful, as one sudden movement can damage the TV device, and the cost of repairing it will increase several times.

IMPORTANT! Dismantling should be done with clean hands, as contamination of the sensor can lead to image degradation.

1. The first step is to remove the T-con, for which first disconnect the cables and remove the bolts. When disconnecting the loop, be careful and keep its shape. Since the cable inside has very thin conductors, any kink or twisting can damage the conductive ability of this part, which will render it unusable.
2. The next step is to remove the protective structure from the decoders. It is a metal case bolted. The user must carefully unscrew the bolts and remove the protection.
3. Remove the front frame of the TV device. In order to do this, it is necessary to unscrew the bolts around the perimeter and carefully disconnect the fasteners.
4. Remove the decoders. To dismantle this device, you must turn the TV over, while gently holding the matrix. Decoders are located on special rubber mounts. They need to be removed. Without damaging the mount, otherwise reassembly will be impossible.
5. Scattering film removal. It is located on special plastic latches, which are enough to snap off, and then remove the film.
6. Remove reflector and retaining clips.

After the user managed to get to the backlight, the breakdown should be specified. To do this, the first thing you need to inspect all the LEDs. Often, due to the fact that several light bulbs violated their functionality, the entire circuit does not work. Most often, the bulbs simply burn out. A burned-out LED is visible to the naked eye. It often has a discolored color, and around it may have a charred surface.

REFERENCE! If it is not possible to detect a breakdown in the eye, proceed with the diagnosis of all LED bulbs.

In order to detect the place of malfunction, it is necessary to connect LEDs to each line. Which line does not light up in the one and there is a problem. After the idle line has been detected, you should start searching for the idle LED. Usually he is one or several. In order to detect them, the user should connect power to each bulb in turn. After inoperative diodes have been detected, they should be unsoldered. For this operation, a soldering iron should be used. After eliminating the inoperative part, a new LED should be soldered in its place.

After the malfunction is resolved, the user should check the operation of the entire backlight, and if everything suits him, proceed with the assembly. Assemble the TV in the reverse order, therefore, first a reflector is placed, then a scattering film, then a decoder, frame, protective structure, T-con and the TV case itself.

What you do not need to do so that it does not break

In order not to damage the “repair” TV device, you should follow simple rules.

1. The assembly and disassembly of the device should be carried out carefully, without using brute force. Often, all devices are removed with a simple click or using the mounting mechanism. If it is not possible to dismantle the part with a light effort, it means that the user either did not unscrew all the bolts or did not remove the mounting mechanism. Excessive use of brute force threatens with additional breakdowns that can render the device unusable.
2. All operations with the matrix should be carried out with clean hands. Since any pollution, even dust, can disrupt the operation of this part.
3. If the user does not have experience and knowledge in this area, it is better not to start the repair yourself.