TV is a pretty important piece of equipment in everyone's home. Like any other complex device, it can stop working for a certain reason. Breakdowns can be different, but the most common is the situation when the TV screen suddenly starts blinking strongly or simply turns off while watching. Of course, this can cause great concern to the owner of the equipment, but you should not worry too much. To begin with, it is important to establish the main reason why the image disappears on the TV, but the sound works.
What are the situations?
There can be many reasons for picture and sound problems. The most common problems that many smart TV owners face include the situation when the image on the LCD TV has disappeared, but there is sound. Additionally, the problem may be expressed as follows:
- TV makes sound but no picture;
- can't change channel properly due to black screen;
- notbacklight functioning;
- technique leads to a strong distortion of the picture, changes its size, leads to the need to change the image format;
- the brightness of the screen deteriorates, the colors become too dull;
- Picture cuts out intermittently and TV screen turns off.
Before you take on the repair of your device, it is important to accurately determine the cause of the malfunction and consider your next course of action.
What problems might arise?
Why does the image disappear on the TV? The most common reason why the picture on the TV starts to fade and the sound disappears is a hardware failure. Problems with the functioning of the power supply or the color unit, a burned-out inverter, a broken matrix and a capacitor - all this for the most part leads to the following problems:
- stop showing all shows;
- picture color changes to green or black and white;
- image changes its position, flips, changes format;
- Other types of problems can also occur when the video itself is missing, but the sound continues to function normally.
The TV has lost the image - what to do? To get rid of such a problem, you should seek help from a private master working in a repair center, or independently search for a problem and its solution.
Cable under test
If sound fromdevice comes out at a normal volume of the audio track, but the TV screen remains dark, then the main solution will be to test the cable that transmits the image:
- antenna;
- HDMI 3;
- from cable provider;
- Checking the Internet connection (this must be done when the TV is equipped with a digital set-top box).
To carry out such a check, you will have to use the special utility Moinfo. It was created specifically to identify the main problems with the functioning of the device when transmitting video signals and sounds. If the application was able to determine the malfunctioning of the device, then the owner should carefully inspect the cable contacts for all kinds of damage.
Problems with matrix operation
Probably the most common reason why an image disappears from the TV screen or a strong change occurs is considered to be a matrix breakdown. If the matrix is damaged, the following symptoms may be observed:
- jumping picture;
- screen starts to show only half of the afterimage;
- bands of different colors or one (pink, white, yellow) begin to go all over the screen.
Most often, the matrix breaks under the influence of external factors, for example, in case of accidental water ingress, falling, or strong power impact. In this case, it will not be possible to repair the screen, you will have to purchase a new matrix (or even buy a new TV).
If problems with such a detail arose for no specific reason, for example, the picture itself suddenly began to become cloudy or double, then this condition can be corrected in the technical service. Here, the old module is being replaced with a new, well-functioning one.
Also, the TV matrix can be replaced independently at home, but it will be very difficult for a non-professional in this area to replace it with their own hands. The first problems will arise already in the process of preparing for the repair: it is not easy to find the right matrix model for a particular TV, it will have to be ordered through the official service centers of the city. Otherwise, there is a high risk of acquiring a fake, which will only negatively affect the condition and functioning of the equipment.
Burnt capacitors in the device
Problems with the operation of capacitors in LCD TVs appear due to strong power surges. External signs of a breakdown may be as follows: the image on the TV suddenly disappears and appears, the screen itself goes out, the signal stops immediately after the device is turned on or after a short period of time, the picture doubles or loses its brightness - darkening, dullness. After disassembling the TV on the board, you can find a swollen or blown capacitor, as well as a blown fuse.
It is important to pay special attention to the fact that after recharging, it is the power supply that fails first. Diagnostic measures should be carried out in the same way as in other situations. TV repair should be carried outan experienced professional who will prevent the complication of the situation and not break it completely.
Matrix cable problems
The main signs by which you can understand that it is the matrix cable that has broken are the following manifestations:
- the picture disappears from time to time on the TV screen;
- the device does not show the image normally - interference occurs, the monitor ripples strongly;
- you can notice the distortion of the picture: a large number of stripes appear on the screen or doubling of the picture in geometric order.
After asking for help from the master, he can offer the following solutions to the problem:
- repair cable;
- Purchasing a new part.
The first method is considered time-consuming and impractical, since it will be much easier to dismantle a broken part and change it to a new one than to try to fix it. You should not try to cope with such a task yourself.
Illumination issues
Another fairly common cause of screen blanking is bad backlighting. In LV devices, the LEDs in the led backlight stop functioning normally. It will be quite simple to identify such a problem - the image blinks strongly, characteristic ripples appear on it, but the main problem is a malfunction in the backlighting of the polymer liquid crystal layer.
Cope with such a problem and fix the backlight with yourefforts at home is almost impossible due to the lack of all the necessary details. Ordering them from an official supplier is too time-consuming and expensive, and such spare parts are simply not supplied to the radio market. For this reason, the best solution is to send your broken equipment to a certified service center with experienced craftsmen.
Inverter burned out
It is simply impossible to describe all the reasons for the breakdown of the voltage inverter on the TV. The main signs of breakdown include the following phenomena:
- picture flickers a lot, distortion appears;
- when you turn on the TV, the picture disappears;
- the video either does not appear on the monitor for a long time or is completely absent;
- TV display becomes dim after turning on and goes out after a short period of time;
- the sound is present, but there are ripples or stripes on the screen;
- The broadcast picture is very blurry, dark, which makes it impossible to determine what is happening on the screen.
The inverter is not only responsible for transferring power to the backlights, but also:
- converts 12 volt DC to high voltage AC;
- restores lamp output current to acceptable level;
- restores the brightness of the picture when you need to increase or decrease it;
- matches the output stage of the inverter and the input impedance of the lamps;
- prevents electronic circuit boards from shorting out too muchreboot.
On their own, only those who know how to properly use a soldering iron and a multimeter, and also have at least basic school knowledge in electronics and physics can fix a broken inverter on their own. It is difficult to answer the exact question of where parts burn out most often, since the problem can occur anywhere: board controllers, lamps, and transformers.
Power supply operation
If the sound of the TV is still there, but there is no picture, but the monitor is constantly blinking, its color is dim, and the image is not displayed correctly or appears very late, then most likely the problem lies in the power supply.
Trying to fix the power supply at home without sufficient knowledge in electronics and physics is prohibited, as this can only worsen the situation and lead to dangerous consequences. It is best to entrust this matter to a professional who will quickly determine the breakdown and repair it.
