The TV turns on but there is no picture or sound

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We offer you TV repair, if there is no picture, but there is sound, from:

One of the most common malfunctions for which our service is contacted is that the image has disappeared, but there is sound. Before contacting the service, try to fix the problem or understand the cause of the problem yourself, here are some simple recommendations.

The problem is in the cable that is connected to the TV

Very often, the reason for the absence of an image can be a non-working cable. First of all, do the following:

  • check the main wires that broadcast the image (HDMI cable, provider cable, antenna cable);
  • check the connectors for connecting the wires, as well as the plugs themselves, for mechanical damage;
  • if during the check it turns out to restore the image, but it is bad or not stable, then you need to check the antenna.

Broken TV power supply

There is sound, but the image does not appear immediately, or does not appear at all. there is a possibility that the problem is in the power supply. Even its initial inspection for a malfunction involves opening the TV cover and checking the power board itself. The correct solution in such a situation would be to turn to professionals.

We do not recommend opening the TV yourself and trying to find and fix the breakdown. This is not only impossible to do on your own, but even dangerous.!

We recommend contacting a specialized service center, a specialist will carry out diagnostics, identifying the real causes of the malfunction, and will offer professional TV repair either in a service center or at home. In any case, complex repairs require the use of special equipment and tools that a good master has.

TV backlight defective

Another popular reason for a picture problem is a defective TV backlight. It is not difficult to check if this is not difficult. turn on the TV in the darkest room and shine a flashlight on the screen. If an image appears in the place where you shine, then the matter is in the backlight.

The inverter of the TV is out of order

No picture when there is sound may be due to a failed inverter. The main signs of a TV inverter breakdown:

  • image broadcast is distorted;
  • the sound appears immediately, and the image is delayed;
  • the image is too dark, the video is difficult to see;

How is the repair carried out?

Modern TVs with a large diagonal are often very oversized, so transporting them to the workshop can be difficult for the owner. There is a risk of damaging the matrix and aggravating the situation, so our masters go home. If there is no picture on the Samsung TV, repairs are usually made on the day of the call, only in rare cases it takes up to a week if the breakdown is serious.

First, diagnostics are carried out, then the cost of the repair is given to the client, after receiving his consent, the master begins work. In this case, the diagnostic fee will not be charged.

The likelihood of contacting the service if there is no image on the Samsung TV

There is no picture on the TV, but there is sound. how to fix the problem

In our time, a rare person does without a TV. Every year, the models are getting thinner, larger and offer more and more new functionalities. Modern plasma screens with Smart TV technology have little in common with devices that were on sale some ten years ago. However, the commonality between the old and new generations still remains. breakdowns and malfunctions still happen. The reasons for this can be very different: blows, falling, ingress of moisture and direct sunlight, or an elementary marriage. In this article, we will take a closer look at what to do if the TV has lost the image, but there is sound. Let’s figure it out. Go!

What to do if there is no picture on the TV

First, it should be noted that such a malfunction occurs quite often in a wide variety of brands of TVs. TVs of all brands are equally susceptible to this: Samsung, LG, Philips, Sony, Panasonic and many others. Therefore, there is no point in blaming the manufacturer.

There are many reasons for the absence of an image on the screen, and you are unlikely to be able to determine it yourself by eye. Most likely, you still have to contact a service center or other repair service. It all depends on the nature of the problem. on this below.

It happens that when you turn on the TV, a splash screen with the manufacturer’s logo appears first (LG, Samsung, Philips, and so on), after which the screen just goes blank. With this, you can change channels and hear the sound. Some users noticed that after a while the image appears, but when you turn it on again, everything repeats and the picture is absent. In this case, try the following tips:

  • Check the connection of the receiver cord as it may have become disconnected. Make sure the cord is plugged in securely. If there is no video signal from the set-top box, many TVs simply turn off the screen.
  • Also, the problem may be in the cable itself. The wire may be damaged or simply be of poor quality. This applies not only to HDMI cables, but also to cables with bells. In them, the transmission of the audio signal and the video signal occurs through separate wires, and the problem may lie simply in a broken wire or its poor contact. In some cases, replacing the wire can correct the situation.
  • Check the power cable. It must also be securely connected.
  • Some users have found a rather original way to solve the problem. to increase the volume to the maximum (or close to it). After a few seconds, the image will appear and then you can set an acceptable volume level.

Please note that all of the above tips will only help if the screen is working. This is indicated by the splash screen when the TV is switched on. If there is no screensaver and the screen is constantly dark, this already indicates that some component of the TV that is responsible for the image is out of order.

There are several components, failure of which can cause no picture on the screen. It is quite common that the inverter breaks down, which supplies voltage to the backlight lamps. The lamps themselves can also fail, and this, in turn, provokes a breakdown of the power supply. In addition to the faults listed above, it is not uncommon for a matrix or motherboard to break down. Also, the problem may lie in the loops, converter and decoder. In this case, non-working parts and elements will have to be replaced with new ones.

It is not recommended to carry out repairs on your own, since modern TVs are rather complex devices, and you risk aggravating the situation even more. If the above simple tips did not help, then the best solution would be to contact the professionals, since the TV will need to be disassembled. It can be a service center of a manufacturing company or a private office, where repairs will be carried out efficiently and quickly.

One way or another, it is impossible to determine what is the reason for the breakdown of your particular TV without a thorough examination. In any case, the device must be disassembled and diagnosed for non-working parts and components. It is best if this is done in a workshop with appropriate conditions, however, if you do not like this option, then many telemasters provide all these services at home.

Of course, replacing some parts can cost a pretty penny, but it should be noted that matrices or motherboards themselves rarely fail. Usually, breakage occurs as a result of physical damage to the part, for example, when the TV falls or gets wet. In general, you cannot do without a telemaster.

Now you know what to do if the TV has lost the picture, but there is sound. You will also understand what could be the reason for such a malfunction. Write in the comments if this article was useful for you, share with other users your experience in solving similar situations, and ask any questions of this article.

Screen frequency changes

Windows 10

  • Right-click on the desktop. There should be displayed two squares with the inscriptions 1 and 2. 1 is your computer or laptop, and 2 is a TV;
  • Scroll down and find “Advanced Display Settings”;
  • Now you need to go to the properties of the second display, go to the “Monitor” tab and set a different frequency. If your TV operates at 60 Hz, then set this. Sometimes you need to set 25Hz to work on older TVs. Click “Apply” and “OK”;
  • Right click on the desktop and select “Screen Resolution”;
  • In the line “Screen” you need to select the second image. so that it is in front;
  • Go to the “Additional parameters” tab. “Monitor”, set the desired frequency and click “Apply”;

Updating Drivers

  • Click on the “Win” and “R” buttons. We register: “devmgmt.msc”;
  • We go to the “Video adapters” section. There we find our video card, right-click and select “Update drivers”;
  • At this point, you should be connected to the internet. Next, select “Automatic search for updated drivers”. We are waiting for the driver to download and install. If the system said that the drivers do not need updating, then you cannot write off rejoicing, since this means that they simply do not exist on Microsoft servers;
  • Therefore, we do it differently. go to the “Properties” of the video card;
  • Next, go to the third tab and select “Equipment ID” in the properties;
  • Copy the first value and go to the site. driverslab.ru;
  • Insert the value into the search bar and click “Find”. Usually the driver will be the very first. so download it. Next, open the archive and run the “exe” file

Correct connection

The best way to fix something is to do it again, but in the right way. Therefore, let’s try to “connect” again, perhaps you are just doing something wrong.

  • Pull out the connected cable and plug it back into the HDMI port and immediately remember which one. I have it at number 2;
  • We connect to any free port on a laptop;
  • Or on the system unit of a personal computer;
  • Now on the remote, you must turn on the button that displays all connections to the TV. It can be a button labeled “Input” or “Source”;
  • Now this section will open in the menu, where all ports and inputs are presented. Choose the one through which you connected your laptop or computer;
  • One more point. on some TVs there is also a menu that indicates the type of device to be connected. This is necessary in order for the image to be of acceptable quality. Therefore, find the button to change the name and select “PC” or “Notebook”;
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If there is no picture on the screen, and you still see this unfortunate inscription, then move on. Also, if there is still an image, but there is no sound, then go to the last chapter.

No image via HDMI on TV or monitor: what to do and how to be

Hello everyone! Today we will talk about a very strange but interesting problem when you connect a laptop or computer to the TV using an HDMI cable, and you see the inscription “No signal” on the screen. The problem is not new and has several solutions. Most often, a connection error occurs either due to hardware problems: for example, when the cable simply leaves in some place.

In other cases, this usually indicates problems with the computer or laptop, and in particular with device drivers. We’ll talk about all this at the very beginning. But first, it will try again to output the signal and images to the TV.

No picture

To see which output mode is worth: you need to press the key combination “Win” and the English key “P”. After that, you should see such a window sweat. Choose one of the last three options. But the best of all is “Duplication” and “Projector only”.

Try disconnecting everything you can from the TV. Including all sorts of TV-receivers, USB drives. This also applies to connections via AV ports. In general, turn it off. that’s it!

On LG TVs, there is a feature that allows you to manage connections. But she also interferes. Press on the remote control on the button with the house icon, then select “Settings”. “Additional. settings “-” General “- scroll down to the function” SIMPLINK (HDMI-CEC) “

No sound

  • In the lower right corner of the screen in the tray, we find the speaker icon and right-click on it;
  • We select “Playback device”;
  • Now you need to select your TV, which should also be displayed on the screen and press the right button, and then select “Use as default”.

If the sound does not appear, then you also need to update the driver for the video card, since often the sound comes from it. How to do it. I wrote above.

Major problems

On the LCD TV screen, picture problems can manifest themselves in several ways. The sign is of great importance. Since the causes of the malfunction are determined according to the.

Mostly, there is no picture on the screen at all, but there is sound. However, there are also slightly different situations:

  • the picture flickers, ripples appear;
  • the video signal periodically disappears, and then reappears;
  • vertical stripes;
  • some elements of the ICE backlight blink;
  • there is an image, but there are defects. stripes or squares;
  • the outline of the picture is green or red;
  • vertical color bars on the screen;
  • viewing is impossible, since the picture is covered by various interference.

There are a lot of reasons due to which the image on the TV disappeared. It is not always possible for users to independently determine the cause of the malfunctioning TV. Therefore, in order to fix the breakdown, sometimes you have to contact service centers.

Image problems appear on both plasma and LCD models. The manufacturer is also not worth blaming. The defects listed above are manifested not only in the work of Samsung TVs. Owners of devices from other manufacturers also face similar problems.

Sometimes the TV turns on and even a splash screen appears, but then the display goes out. Sound is present and channels are switched using the remote control. The main reasons for this failure:

  • the inverter is faulty, providing voltage to the LED backlight elements;
  • the presence of irregularities in the operation of a convector, loop or even a decoder;
  • mechanical damage to the matrix, motherboard or backlight element;
  • problems with electrolytes that are in the power supply;
  • the electrolytic capacitor has broken;
  • the matrix cable has come off, providing connection to the board.

Breakage of any loop can lead to such a malfunction. To surely establish the cause of the TV’s malfunctioning, you need to seek help from specialists.

In old TVs (CRT models), this kind of defects appeared due to problems with frame or line scanning.

Why is there sound on a Samsung TV, but there is no picture

The reasons that there is sound on the Samsung TV, but the picture is not, may be software and hardware failures. Why do such breakdowns occur? Power surges, mechanical damage, improperly installed applications or updates. all this can lead to incorrect operation of the TV.

If the TV stops working, this does not mean that you need to contact a service center. You can fix some problems yourself. Now we will analyze the main reasons for the appearance of problems with the image, as well as explore ways to eliminate the error that has arisen.

What faults can be eliminated by yourself

Useful tips from professionals in case the TV screen turns off, but there is sound:

  • Check the integrity of the connecting cable. If the wire is broken or damaged, replace it with a new one.
  • Increase the volume to maximum, after that the black screen may disappear and the TV will start working as usual.

On the rear panel, check that the antenna cable is properly connected to the corresponding jack. The plug may be damaged.

Check the TV settings, it is possible that the image disappears due to incorrectly set parameters. Return to default settings.

The above recommendations are relevant only if the screen is in working order. How can I check this? Turn on the TV, if the splash screen appeared immediately after launching, and then disappeared, then the problem lies in the wrong settings or connection (in this case, a lot depends on the signal source). Users will be able to eliminate such problems on their own.

Blue screen, white screen and all sorts of other malfunctions can also appear due to faulty hardware modules that burn out due to short circuits. To prevent such breakdowns, get an uninterruptible power supply.

If, after turning on the Smart TV, the picture disappears, and the sound disappears, then first of all you need to check the functionality of the wire. This can be done using the Moninfo program. The software is designed to check the quality of transmission of various signals (audio, video).

If the software detects abnormalities, then the problem is with the connecting cable. To check the quality of your video signal, follow a simple step-by-step guide:

  • On the remote control, press the button with the house icon.
  • Go to the settings menu.
  • Select the “Support” section, and then the “Self-diagnosis” tab.
  • Activate the command “Run Image Test”.
  • After the end of the diagnosis, a list of recommendations from Samsung will appear, use them.

We will also consider other problems, as well as analyze ways to eliminate them.

The image is flickering or the brightness has decreased.

Deactivate the “Energy Saving” command or deactivate the “Eco” mode.

Check if the cable is connected correctly.

The image is too dim on the screen.

Adjust the brightness in the “Advanced settings” menu.

The picture is split in two, blurry and shaky.

Disable any additional energy saving features.

Check the quality of signal reception, the cable or antenna may be damaged.

Disconnect the antenna cable and then reconnect it.

Roll back to the default settings.

A dotted line appears along the edges of the display.

Change resolution, switch to 16: 9 aspect ratio.

Almost all types of problems can be fixed by yourself at home. Without the use of professional equipment. It is much more difficult with hardware breakdowns, since in order to replace a broken part, you need to disassemble the TV.

When to contact the service center

Self-repair is limited to software and cable problems. Complex hardware breakdowns, due to which there is no image on the Samsung TV, it is more expedient to entrust the service center masters.

The most common failure is an inverter failure. This module provides voltage to the lamp, and it also controls the start of the backlight. The investor is represented in the form of one or more blocks of microcircuits. It all depends on the TV model. The component is located next to the power supply.

Before proceeding with the repair, specialists check the presence of the incoming voltage. Ripple should be absent. After this, the wizard looks at how the command goes to start the lamps from the motherboard. Mostly the failure appears at this stage.

If no breakage is found, the backlight elements are replaced. Re-testing is underway. If the system is working properly, the repair is completed.

Sometimes the problem does not go away after replacing the lamps, which means that the problem is much more serious than it initially seemed. First, a visual inspection is carried out. Experts are trying to determine the presence of burnt links.

Field-effect transistor switches break quite often, but replacing them may not give a result or will solve the problem for a short period of time. The fact is that changing the keys eliminates the consequence of the malfunction, and not its cause. Therefore, the defect occurs repeatedly during the subsequent operation of the TV.

Another weak point of inverters is high voltage transformers. These elements are heavily loaded. Accordingly, normal wear and tear occurs extremely quickly. Replacing transformers also solves the problem.

The second type of hardware failure is the backlight. Engineers simply replace faulty lamps with original parts. The absence of an image may be a consequence of cathode burnout. This problem is corrected as follows. The bolts securing the board are unscrewed. The opening of the matrix is ​​not carried out, since the masters use a special tool that allows you to turn off the component. Dust will not get inside the matrix.

Manufacturers of TV devices assure that the lamps need to be replaced exclusively with the matrix. The lamp is turned off as carefully as possible. Basically, the part is glued to other elements of the system. High temperature causes the lamp to be soldered to the microcircuit.

The loop that connects the lamp to the board is turned off, and only then the component is removed. The new lamp is fixed in the same way.

A burned-out power board is another reason that there is sound, but there is no picture. This component has several forms, it all depends on the size of the TV-device. For example, compact models are equipped with block-shaped boards. Large TVs are equipped with a chassis board. The service center technicians will quickly disassemble the TV, and then change the faulty elements.

The weak point of any power board is the filter capacitors. When the damaged elements are replaced, the power supply, lamps and inverter are connected.

Hardware repair is indeed a very expensive procedure, but trying to change the inverter, lamps or power board yourself will worsen the problem. Therefore, it is better to contact the service center.

Why is there a black screen on the TV, but the sound remains?

You are faced with such a problem on TV: the TV screen is black, but there is sound. Naturally, due to this malfunction, viewing the programs is not possible. In this article, we’ll show you what to do about this problem. What caused the picture to disappear? Let’s look at the internal and external causes of the problem.

  • To understand what went wrong, the first thing: we look at the equipment. If the equipment is completely new, this malfunction may appear due to the manufacturer’s defect.
  • If the device has served you for several years, there is a possibility that the batteries or backlights are out of order.

It follows from practice that the technique itself most often has absolutely nothing to do with it: this malfunction is not always the result of equipment failure. Uninterrupted image reproduction depends not only on internal elements (boards, circuits, blocks), but also on external ones (antenna cable, distribution box, etc.)

Don’t be discouraged if you just see a black screen when you turn on the TV.

There is a possibility that the solution to the problem is very close:

  • Antenna cable (cord);
  • Distribution box;
  • Plug;
  • An external antenna located on the roof is the most vulnerable element in this problem.

Inspect these items, especially the plug. Basically, it is connected from the back to a special connector (socket).

First you need to pull it out of the connector and insert it back. There is a possibility that due to poor contact, the signal coming through the plug is weak. This could be one of the sources of image fading.

Next, you need to connect a second TV (of course, a working one) to the antenna wire in order to check the signal quality.

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If, after connecting, a poor-quality signal began to arrive or there is simply no image, then most likely the problem is either in the external antenna or in the antenna cable.

If there is a problem with the external antenna, then it remains only to call the organization responsible for its maintenance.

Proper handling of the TV is the key to its long-term service.!

Often equipment breaks down due to improper operation.

Unscrupulous attitude to the appearance of minor malfunctions, mechanical stress, penetration of moisture into the body. all this leads to wear of the components, as a result of which malfunctions appear.

One of the most vulnerable spots in modern TVs is the inverter. This part often fails. An inverter is an expensive part, so a specialist will most often recommend repairing it rather than changing it. This problem, for which the picture is missing, is typical for TVs of LG and Samsung models.

Why does a black screen appear on TV and sound works

Try to find out if your TV has a mute function. This is true for newer LCD / LED TVs such as:

  • Philips (Philips);
  • Toshiba (Toshiba);
  • Sony (Sony);
  • LG (LG);
  • Samsung (Samsung).

Certain TVs have the ability to turn off the picture: this function allows you to listen to the sound of the TV or DVD player when the picture is turned off on the screen Make sure not to enable this function.

TV turns ON but no picture or sound UPDATE black screen FIX

But if we exclude all factors from the outside, then only the problem remains at the hardware level. Let’s take a look at what’s the matter.

A common cause of malfunction of new TVs, due to which the image disappears when there is sound, is the failure of lamps or screen backlight LEDs.

The easiest way to determine whether the problem is in the backlight or not is: take any light source (lamp, hand-held flashlight, or even a flashlight on your phone) and, with the TV turned on, bring the light source to the screen.

If you see that the image is there, but it is very difficult to see, then your lamps or LED strip are out of order. Of course, there is a possibility that the color module, power supply, frame and line scan unit, tuner or matrix are out of order.

If you are not an expert in this matter, it is quite difficult to replace or repair the listed parts, therefore, this work should be carried out only by a TV repair specialist.

What is the reason for the disappearance of the image on the TV screen connected via HDMI?

Let’s just superficially touch on the connection via HDMI of a computer to a TV. In rare cases, with this connection, the image may disappear quite often. The first thing to do is test the HDMI cable itself. Also check if hibernation is running on your computer.

The sound can also be played, but the picture will never be. Basically, everyone can cope with the HDMI cable connection, and this is not a serious problem if you have a whole and working HDMI cable. But this issue also has its own pitfalls that the user may encounter.

So what to do. If you do not have an image when connecting, check the cable for kinks, bends, breaks, if there is such damage, you need to replace the HDMI cable.

You also need to check the settings and make sure that the computer has not entered sleep mode. Another option is connector failure. In this case, you need to refer the technician for repair to specialists.

These are the main reasons due to which, when the TV is connected via HDMI, the image is not displayed.

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Indicator shines red

The situation when the TV cannot be turned on from the remote control or buttons on the device itself, and the indicator is on, is common. Usually, in such cases, they say: “The TV does not come out of standby mode.” There may be several reasons for this, but you need to start with the most obvious ones. Replace the batteries in the remote control, remember from which button the TV was turned on earlier and, if this does not help, call the master on the TV or, with the proper skill, start an independent TV repair.

The glow of the indicator is more or less likely to indicate the health of the power supply. However, the diagnosis of this malfunction, like most others, should be started with an analysis of the operation of this board. Checking voltages in standby mode, their stability when trying to turn on in the operating mode, measuring the level of filtration, visual inspection of parts helps to assess the health and functionality of the power supply. Electrolytic capacitors, the upper part of which has a characteristic swelling, must be replaced.

In the section “Malfunctions of TVs”, the real history of repairs of TVs with a similar manifestation of a defect is considered on the example of TVs Philips 42PFL7433S / 60, Samsung LE40R82B, Philips 20PF5121 / 58 and other models. The behavior of television sets was somewhat different, but the reason was the same. There was a change in the properties of electronic components, mainly capacitors, in which the power supply could not provide a confident start, affecting the operation of the entire system so that the indication was present, and the TV did not turn on. If in one case the malfunction was visible to the naked eye, then in the other, its localization required a long process of diagnostic measures and measurements.

The elimination of an obvious defect in the power supply does not always lead to normal operation of the TV as a whole. In some cases, unstable power supply leads to loss of information in Eeprom, SpiFlash memory chips. At the same time, it is possible to turn on the TV and switch it to operating mode only by updating the software (firmware) on the programmer. The workshop is equipped with these devices in sufficient quantity for different types and cases of microcircuits. When repairing with your own hands, difficulties may arise with firmware without equipment and a firmware database for television models, and contacting a service organization in such a situation is morally and economically justified.

Sometimes such troubles occur when there is a malfunction in the power circuits on the TV’s motherboard. Usually in this block there are several secondary sources, made according to the scheme of DC-DC converters or voltage stabilizers. An indispensable condition for the correct operation of the processor and devices associated with it is a stable supply voltage in the voltage range at which their normal functionality is ensured. In cases where these conditions are not met, the consequences can be unpredictable, and the command to turn on the device can be ignored until the necessary power supply parameters are provided.

The indicator (light bulb) constantly blinks chaotically

This state of the device only indicates a malfunction and does not contain significant information about possible problems. It is necessary to diagnose the entire device, starting with checking the power supply and secondary converters on the system board. Further, the buses for the exchange of information between the processor and memory microcircuits, the sending of commands by the processor to turn on and the processing of these commands by the peripheral components of the television chassis are investigated.

The indicator turns green, but nothing happens

The situation is ambiguous and can have many reasons for this behavior. In order to make sure that the main board is working, the supply voltages are measured and the commands to turn on the power, backlight, etc. are examined. Perhaps, when you switch the TV to a channel with a tuned program, a sound will appear, and this already indicates that the cause of the malfunction most likely lies in the inverter or power supply unit with LED backlighting or in radiation sources.

TV turns ON but no picture or sound black screen FIX

If the LED (light bulb) indicates the operating state, but the power-on commands are not received from the motherboard, the system does not respond to the buttons and the remote control, the software of the memory devices on the main board may fail. There are situations when the processor issues a command to turn on the power supply, but does not start the inverter, or issues a Dimm command, which determines the brightness of the backlight, in the absence of an On / Off command. In this case, software updates, firmware help to return the normal sequence to the logical processes occurring on the motherboard.

In some cases, the appearance that nothing happens when turned on can be created by the motherboard, blocking the supply of signals to the matrix controller or transmitting such information in which the screen remains dark. The T-con itself may be faulty, as well as the LCD matrix itself. Each option is considered and diagnosed separately. At the same time, the backlight turns on, but has a weakly pronounced character due to the underestimated image brightness.

The indicator changes color to green and back to red

This behavior most often indicates that the processor generates a command to turn on the device and sends it to all executors. If any of the TV units does not follow the command, for example, the power supply does not turn on in operating mode or the inverter is not able to start the backlight, then the processor, not receiving confirmation that everything is in order, cancels the power on and puts the device back into standby mode. In Sharp LCD TVs, after five unsuccessful attempts to turn on the backlight, the processor blocks the startup altogether, until the errors are cleared through the service menu or until the contents of the Eeprom memory are replaced. This behavior will continue until the cause is eliminated: defective lamps replaced, inverter, power supply, or other faulty component of the TV chassis repaired.

The indicator flashes in a specific sequence

In television receivers of some manufacturers: Sony, Philips, Panasonic. self-diagnosis of the TV is provided at the moment it is turned on. As a result of polling via SDA, SCL buses, the central processor receives information about the operability of other functional devices: tuner, sound processor, memory chips, the digital bus itself, etc. If a faulty node is detected, the turn-on command is blocked, and the receiver goes into standby mode with error indication. The light indicators start blinking in a certain sequence, indicating a particular error in the device.

This self-diagnosis method allows you to quickly identify the faulty component. The service instructions for a specific model contain the so-called error codes, in which each combination of flashing indicators corresponds to possible failures of various components of the TV receiver. This greatly facilitates the life of the telemaster when diagnosing, directing him along the right path. For example, a paused 13 LED blinks on a Sony TV on a FIX2 chassis indicates a backlight problem. An inverter or lamps can be faulty, so we will diagnose them. As an example, I will give a table with error codes for Philips TVs on the Q552.1E LA chassis. The first level of errors (Layer 1) we see immediately when a defect occurs, the second level (Layer 2) can be observed if the receiver is switched to service mode.

Summing up, we can say that the behavior of the indicator light in the TV when a malfunction occurs can give a lot of useful information for the successful diagnosis and localization of a defect in a particular unit, contributing to the successful repair of the TV as a whole.

There is no picture, there is sound

If there is no picture and there is sound in the TV with LCD or LED backlight, you should pay attention to the fact that the product is almost fully functional: it is controlled from the remote control and from the front panel, there is sound control, but the screen is dark. In most cases, the “culprit” is the LED backlight power supply unit or the LCD panel inverter, as well as their operation in protection mode in the event of LED or lamp failure. Less commonly, there are problems with the power supply or the lack of a power-on command from the motherboard.

Among the typical defects that fall into this category, one can note the failure of the BD9897FS PWM controller chip in Philips TVs made on Master and Slave inverters, breakage or burnout of light-emitting diodes in the Samsung TV backlight strips of the UE32F50XX series, interturn short circuit or breakage of inverter transformers in all LCD TV receiver models. It should be mentioned that there are a large number of TV types from different manufacturers, in which the correct operation of the backlight unit is monitored by the central processor, and if this unit fails, an error signal is sent to the motherboard, blocking the operation of the entire device or putting it into self-diagnosis mode. This is visually indicated by flashes of the emitting diode on the front panel. The sound channel in this mode is blocked by the processor.

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The absence of a picture can be caused not only by a malfunction of the backlight. Sometimes the dark screen can be caused by other parts of the TV: main board, matrix controller or LCD panel. In this situation, the backlight works, but the image is not displayed, which may be due to various reasons. From a failure in the software of memory chips on the motherboard to a malfunction of the reference voltage generator for the DAC drivers, defects in the voltage generation unit for supplying drivers in the T-con, or failure of the LCD matrix elements. There are no ready-made recipes in this case. Only an analysis of the functionality of individual nodes and sections of the circuit, diagnostics of their condition, electrical measurements will help find the right solution for restoring the device.

The TV has no picture or sound

A professional telemaster in his work always uses a creative, comprehensive approach when diagnosing various kinds of malfunctions, including defects associated with the absence of an image in the presence of sound and vice versa. To determine the source of the breakdown, it is necessary to assess the general state of affairs, without losing sight of a single detail. Almost always, in case of a malfunction of a well-functioning mechanism, which is a modern TV, in addition to the main problem visible to the naked eye, there are also minor nuances, the knowledge and identification of which contribute to the success of the business, helping to localize the weak link and calculate the affected area of ​​the electrical circuit.

Invaluable help in analyzing the situation is provided by a specialist’s knowledge of typical malfunctions of this model and the chassis of the device. It is no secret that certain series and brands of TVs have “diseases” inherent only to them. Possession of this knowledge helps to carry out diagnostics at lightning speed, find a “burnt out” part and carry out its replacement, “transferring the patient from intensive care to the convalescent ward.” However, the range of possible conflicts arising in the device is so extensive that only a small part of them can be subject to such “treatment”. For the rest, the only solution is painstaking work on assessing the functionality of individual nodes and sections of the circuit, analyzing their condition, electrical measurements, taking into account minor factors that help to get the overall picture and direct the master in the right direction.

There is no sound, there is an image

Investigating the problem of the absence of sound in a normal picture, we can say that there is no wide range of typical malfunctions. Exceptions include the breakdown of electrolytic capacitors and smd components in the power circuits and strapping of the audio path microcircuits and the frequent breakdown of the dynamic heads. Sometimes this defect is observed due to a software failure in memory chips (EEPROM, SpiFlash) and to restore their original properties, they need to be flashed on the programmer or replaced with chips with installed software. Otherwise, the absence of a sound signal is purely individual in each case. Electrical measurements of the operating modes of ULF microcircuits, sound processor and other elements involved in the procedure of demodulation, conversion and amplification of the audio component of a television signal will help to localize the problem.

A telemaster in search of solutions of this kind is helped by an understanding of the essence of what is happening, knowledge of circuitry, the ability to analyze and an extensive knowledge base of similar faults and methods of restoring equipment. Most of us are guided by the principle in our practice. “Do no harm!” Extreme accuracy and caution when taking measurements, anticipating the consequences of your intervention has become the norm for a qualified approach to repairing TVs. We strongly recommend that people who are far from this profession do not expose their TV to stress trying to fix it on their own. Believe me, this is not so easy in modern high-tech models. We often hear the phrase: “I just don’t have a soldering iron (circuit, tester), otherwise I would fix it myself.” and silently hide a smile. Self-repair is certainly possible, but it comes down mainly to replacing “swollen” electrolytic capacitors, easily diagnosed with a cursory visual inspection, or following advice gleaned from telemasters forums and electronic repair resources. Our pages reveal some secrets of TV repair, whether to follow them or not. you decide.

Matrix loop

Sometimes the image on the LG TV disappears due to damage to the matrix cable. Breakage manifests itself in the following signs:

  • the image periodically disappears;
  • unsatisfactory picture quality. noise, ripples appeared;
  • there are horizontal or vertical black-and-white, colored stripes.

The specifics of the elimination of the breakdown will directly depend on the specifics of the damage to the loop. If the malfunction was detected at an early stage, then the service center masters will rewire the damaged sections of the loop, restoring the TV to work. In some situations, you have to change the matrix cable completely.

The second option is considered a more durable solution to the problem. A soldered loop will work for a relatively short time. Therefore, it is wiser to immediately change it to the original component. You should not do this on your own. Entrust the work to professionals.

Broken cable

If the quality of the audio signal does not raise any questions, and there is no picture, it is imperative to check the integrity of the connecting elements. It’s about the cable. Which one? The answer to this question depends directly on the signal source. Therefore, you need to inspect:

  • antenna cable;
  • HDMI wire;
  • cable connected by your cable TV provider;
  • Ethernet cable (provided that you are using Smart TV).

Use special software to determine the cause of the black screen. For example, the Moninfo utility. It helps you identify audio and video problems. If the program detects malfunctions, you must carefully inspect the cable for damage.

What to do if a picture is missing on your LG TV, but there is sound

Users encounter such a failure quite often. Run diagnostics to determine why there is no picture on your LG TV, but there is sound. Mostly the reason lies in the malfunction of the hardware modules. However, in no case can you rule out software failures.

Users can fix some defects on their own. complex breakdowns requiring a full disassembly of the TV are best left to the specialists of the service center.

Burnt out power supply

If there is sound, but the picture is constantly twitching, the screen is dark, the brightness has dropped, other defects have appeared, then the power supply unit of the LCD TV is not functioning correctly.

Users who do not know how LG LED TVs work should never try to repair them on their own. Call a specialist who will be able to quickly determine the reason for the incorrect operation of the TV.

However, the diagnosis can still be carried out independently at home:

  • Start by discharging the capacitors. Unplug the TV from the wall outlet. Unscrew the fixing bolts, and then remove the rear cover. Check cables and loops, some of them may be damaged. Be sure to test the functionality of the buttons and fuses.
  • Inspect the power supply for melted or charred resistors, capacitors. If there are such elements, then they must be replaced immediately.
  • Measure the voltage of the output circuits of the power adapter. The obtained indicators must correspond to the parameters that are indicated on the board or in the documents of the equipment.
  • Voltage drops. For example, the voltage level reaches 200V, find the cause of the breakdown in the primary power circuit.
  • If you knock on the TV case, and the image has returned to normal for a few seconds, then the problem was caused by poor-quality soldering of the power supply elements.

Soldering contacts and other elements must be carried out with professional equipment. The use of improvised means is fraught with the aggravation of the original malfunction.

Burnt out inverter

Due to the fact that the inverter has broken down, the TV screen stops working. Breakage symptoms:

  • distortions appear, the picture twitches;
  • the image is missing in principle or takes a long time to load;
  • TV display dims after switching on and instantly goes out;
  • sound is transmitted correctly, but ripples appear on the screen;
  • the picture is very blurry, low brightness level.

The main function of the inverter is to supply voltage to the backlight lamps. Therefore, if the TV screen does not light up, then perhaps the reason lies precisely in the malfunction of the inverter.

  • conversion of direct (12-volt) voltage to alternating;
  • stabilization of the input current of the lamp to the required values;
  • adjusting the brightness level of the image;
  • matching the output stage with the input tube resistance;
  • protection of microcircuits and boards from possible short circuit, overload.

How to determine if the problem with the absence of an image is caused by the failure of the inverter? It is necessary to disassemble the TV and conduct a comprehensive diagnosis. The breakdown of the module can be determined during the visual inspection.

To restore the TV, you need to have at your disposal a hot air and infrared soldering station, as well as a multimeter. A good knowledge of physics and electronics is also required. It is extremely difficult to say which element has failed. Incorrect operation of the TV can be caused by a breakdown of the lamp, transformer, controller board.

Capacitors burnt out

In LCD TVs, capacitor problems are caused by power surges. Signs of a defective capacitor:

  • the picture is double;
  • there is no image;
  • the TV turns off arbitrarily;
  • low brightness level;
  • incorrect color rendering.

In order for the device to start working correctly again, you need to disassemble it. On the board, you will see a damaged capacitor and a blown fuse.

If the breakdown is not eliminated in a timely manner, the malfunction will worsen. After a while, there will be irregularities in the operation of the power supply. The set of procedures aimed at diagnostics is identical to the situation with matrix breakage.

Replacing capacitors is a complex type of hardware repair for TVs. The slightest inaccuracy will provoke an aggravation of the malfunction. Therefore, it is wiser to entrust the elimination of the malfunction to the specialists of the service center.

Reasons for the disappearance of the image

The most common reason for the disappearance of the image on the LV TV is hardware breakdowns. What to do in such situations? How to restore the correct broadcast of digital or analog TV? It is necessary to carry out diagnostics to determine the failed module.

Immediately after identifying a damaged component, it must be replaced. You can do this yourself. However, this option is relevant, provided that you have the necessary skills and equipment. If you do not know how to repair TV, then contact the service center.

turns, there, picture, sound

Now let’s go directly to the consideration of the main reasons for the disappearance of the image.

Failure of the matrix

Matrix breakage is perhaps the most common reason that there is no picture on the TV screen. Also, damage to the matrix can cause a number of other symptoms:

  • video shakes;
  • the image is displayed only on half of the screen;
  • various stripes appear around the perimeter of the screen.

Why is the matrix not working? The component fails due to short circuits and mechanical damage. It is impossible to repair a faulty matrix. Therefore, a part is replaced. If defects began to appear for no reason, for example, the image darkened sharply. The matrix elements are probably damaged, their replacement is much cheaper than the entire module.

Can you change the matrix yourself at home? This is theoretically possible. However, it will be extremely difficult for a person who has never repaired televisions. In addition, instead of the broken part, you need to install the original matrix. It is very difficult to buy branded components.

turns, there, picture, sound