There Is No Picture On The TV, But There Is Sound: What To Do If The Picture Disappears, But The Sound Works? Why Doesn't The Screen Show?

2024 Author: Beatrice Philips | [email protected]. Last modified: 2024-01-18 12:09

Nowadays, few people do without a TV, while progress does not stand still, every year the offered models become thinner and thinner, manufacturers present more and more advanced functionality - modern panels have very little in common with those devices that were sold for another 10- 20 years ago. However, much has remained unchanged - breakdowns and malfunctions happen as before. In our article, we will dwell in more detail on the situation when the sound comes from the TV, but the image does not appear.

Possible causes and diagnosis

To begin with, we note that such a breakdown is by no means uncommon for TVs of various brands. Such a malfunction is equally susceptible to equipment from Samsung, Philips, Sony, LG, Panasonic and many other brands, so there is no point in blaming the manufacturer . The first step is to determine which hardware module is not working correctly.

To do this, you need to perform an analysis of the symptoms of the malfunction. The fact of the absence of an image manifests itself in different ways.

For example, the TV screen may go out and turn on, or ripples, blackouts, dark spots, streaks, or any other spots appear. The most common signs of such a malfunction are:

• there is sound on the TV, but at the same time the audio sequence has ceased to be broadcast;
• the screen remains completely dark if you turn off the sound, it may seem that the technique is not working;
• the picture is distorted - in this case, stripes appear on the screen, they can appear immediately after turning on the TV, or they can make themselves felt already in the process of work;
• monochrome image - the screen did not go out, but turned white, green or red, no dynamic scenes or any other changes are visible, only one shade is displayed;
• the broadcast is carried out, but at the same time a large number of all kinds of defects and interference , which make comfortable viewing impossible;
• the audio sequence periodically disappears , the intensity of the glow or the level of brightness can change - such a failure can be present constantly or from time to time.

There are many reasons that lead to the absence of an image on the TV screen. It is impossible to determine them "by eye" on your own. In most cases, contacting a service center or any other repair shop is required. In this case, the methods for diagnosing and evaluating equipment directly depend on the nature of the problem. This will be discussed below.

Network problems

Quite often, disturbances are caused by changes in signal levels. This happens especially often under adverse weather conditions: during rain, thunderstorms or lightning. In this case, no special measures are required, after a while the situation will normalize by itself. If the weather is calm, try to check the connection of the receiver cord - if it is disconnected, the equipment will not work. You can eliminate such a malfunction on your own at home, even without any special knowledge in the field of physics and electrical engineering.

Checking the cable

If the image on the TV screen is disturbed, special attention should be paid to the cable. It is possible that the wire was damaged or its quality was initially so low that it led to a malfunction. One of the effective measures for diagnosing the health of cables is testing all wires that transmit the picture:

• antenna;
• from a cable provider;
• HDMI.

If we are talking about digital set-top boxes from providers, then you need to make sure that the Internet is available.

This requires a special Moninfo utility , it is used to detect various problems in the process of transmitting audio and video signals. If the application fails, you need to carefully examine the wire for damage, as well as inspect the cable contacts.

Matrix problems

One of the most common reasons why the TV screen does not light up is a matrix breakdown. The problem manifests itself as one of the following symptoms:

• the video starts to skip;
• an afterimage appears on the screen, occupying only a portion of the monitor;
• there are stripes all over the screen: they can be yellow, white, pink or multi-colored.

In most cases, such breakdowns are the consequence of a negligent attitude to technology . So, the falls of the TV or severe mechanical damage lead to malfunctions. The broken part must be replaced with a new, workable one. However, sometimes it is so expensive that it is easier to buy new electrical appliances - the cost of the matrix is often comparable to the price of new equipment. If you are determined to replace a module, then keep in mind that to do it yourself, without having the skills to work with the technique, will not work . Moreover, problems can arise even at the stage of selecting suitable spare parts.

Burnt capacitor

With voltage drops in the network, the capacitor often fails . In this case, the image suddenly fades and is replaced by a black screen. Typically, this problem occurs a few minutes after the start of the job. There is also a situation when the picture is saved, but it becomes too dark, the audio signal is not transmitted correctly. Quite often, the fuse stops working at the same time as the screen, in which case the picture starts to double.

To determine the malfunction , it is necessary to remove the rear cover of the equipment . Inside, you will see that the capacitors are swollen, in some cases they can even explode. The repair of such equipment cannot be postponed - if the device is left without timely repair, the situation will only worsen and cause an interruption in the operation of the power supply.

We test the matrix cable

If the screen does not light up, then it is imperative to check the matrix cable. You can diagnose such a malfunction from time to time appearing noises during broadcasting and distortions on the screen … Repair of this element, as a rule, is not carried out in service centers, the part is completely replaced with a new one.

Please note that the matrix cable is very fragile, it can be damaged without even exerting any physical effort.

In most cases, doing it yourself will only make the problem worse . A much more practical option would be to replace the failed cable with a new one - in this case, the TV will work correctly for several more years. While re-soldering this loop, its work will still be extremely short-lived.

Backlight

The disappearance of the backlight in the TV often causes the cessation of the transmission and broadcast of the video sequence, while the sound remains completely intact. To fix the problem, take a small flashlight and point it at the darkened part of the screen: if, upon close examination, you notice any objects, then this will be a direct signal of a malfunction … Signs that the backlighting lamp is out of order include the appearance of white and dark spots on the monitor.

Modern manufacturers inform that the illuminating lamp can only be replaced together with the matrix . Such repairs cost the owner of TVs a round sum, so it makes sense only if we are talking about expensive equipment initially. When a TV of a simple model requires repairs, it may make sense to purchase a new one.

If the reasons for the absence of an image on a television screen are in the malfunctioning of the illuminating lamps, then the diagnosis can be easily and simply carried out on our own . To do this, the TV should be brought into a dark room, turned on and shined on the screen with a flashlight. If a picture appears in the place where the light beam is directed, it means that the cause of the malfunction is precisely in the lamps.

Determining the cost of replacing parts is not easy, since the price of spare parts, depending on the TV model, can be either affordable or quite high.

Anyway lamps can only be purchased from official suppliers . If you buy low-quality parts, they will fail very quickly, and the device will have to be repaired.

Inverter

In a situation where there is sound on the TV but there is no picture, be sure to check the functionality of the inverter - when this part is broken, the broadcast is distorted. If the TV turns on, then the sound first appears, and the picture appears on the monitor only after a few minutes. Sometimes the brightness of the image is so low that it is possible to see what is happening with great problems, or it does not work at all. Besides, an indirect sign of a malfunction of the inverter elements is a constant ripple on the screen.

Power Supply

If the TV says, the picture did not disappear at all, but simply became dim or is displayed on the monitor with a delay / constantly twitches, then usually the cause of such unpleasant phenomena is the failure of the power supply. Any manipulations performed with a power supply unit by a person who does not have specialized knowledge in electronics and technology is categorically unacceptable. However, you can perform an initial inspection to diagnose problems. To do this, follow these steps.

First of all need to discharge capacitors - to do this, remove the plug from the socket. Then you should open the back panel, check the wires for breaks and kinks. Special attention should be paid to checking the buttons and fuse for operability. Inspect the power supply, it is possible that you will see melted or swollen capacitors or resistors - if they are found, they must be replaced immediately.

Using a multimeter measure the voltage of the output circuits of the power supply module , their parameters must match the values indicated on the board or in the accompanying documentation. If the voltage differs from these values and approaches 200V, then the cause of the breakdown must be sought in the incorrect operation of the primary circuit. Tap the TV. If at this time the video picture starts blinking or changes color, it means that the problem of the breakdown is low-quality soldering of wires or modules, only it needs to be repaired.

How do I fix the problem?

Before proceeding with the self-repair of a failed TV, it is important to individually assess your abilities and knowledge in working with electrical engineering . If you do not have the appropriate skills, then it will be dangerous to repair a broken device. If you have any doubts, you should give up trying to cope with the problem on your own and contact a certified center. The fact is that new models of television equipment are very complex, and improper operation can damage the TV.

However, there are some types of work that do not require qualified assistance, for example, replacing the cable. Observing the instructions, it is not difficult to do this. As a rule, the user does not have any difficulties and problems with the process of finding a replacement for a failed part and during the repair itself.

You can try to turn off the TV and restart it after a few seconds .- if you are dealing with system failures, then this way you can eliminate them. In addition, you can try to increase the volume to the maximum - in some situations this leads to normalization of work. If voltage fluctuations and sudden surges in the network became the reason for the failure of equipment, then it is worth installing an RCD or another uninterruptible power supply - this will streamline the operation of the equipment.

Decrease in screen brightness is often caused by enabling power saving mode … If you turn it off, the picture will return to its colors and become well and clearly distinguishable, you can adjust the value of this parameter through the settings. This is the list of manipulations that you can perform yourself if your TV screen goes out, is exhausted. In all other cases, it is better to entrust the diagnostics and repair of your equipment to the specialists of the service center.

Recommendations

The help of the wizard is necessary if you cannot determine the cause of the equipment malfunction on your own. In this case, you can call a specialist at home or take the TV to the center or repair shop yourself. If the matrix fails, it is almost impossible to repair the equipment on your own.

Moreover, it is practically very difficult to find suitable spare parts, and, in principle, very few people can correct such irregularities in the operation of the TV.

You should not try to repair the loop of the liquid crystal matrix, as practice shows, it is better to immediately change this part to a new one .… You also need to contact the master if you need to replace the capacitor and when there are problems with the backlight. In the absence of sufficient competence, it can be very dangerous to independently replace parts, even small inaccuracies in the operating technology lead to the destruction of the electrical appliance and cause a malfunction, in addition, they can cause electrical injury in the future.