What could be better than an evening watching a movie on TV? For many, this has become an ideal pastime, so it’s especially disappointing when your favorite equipment stops working properly. A white screen on a TV is a fairly common problem that requires immediate repair.
“Polite Service 5+” is a company that will help bring broken equipment back to life. Our team consists of exclusively professionals with extensive experience in repairing electrical appliances and electronics of any complexity. We work without breaks and days off from 7:00 to 23:00, so you can contact us at any convenient time. You can submit a request for TV repair by phone or on our website.
Causes of malfunction
It is impossible to independently diagnose what caused such a breakdown. You will need a master with professional equipment. The reasons for the appearance of a white screen when turning on or trying to change the channel differ for different types of TVs.
LCDs are characterized by:
- matrix malfunction;
- electronic defect;
- broken firmware;
- broken processor.
If a whitish screen appears on CRT television equipment, the faulty video amplifier is to blame. In plasma TVs, signal processing units are usually the first to suffer.
A separate category includes manufacturing defects, mechanical damage, moisture, or too long use. In some cases, it was possible to repair the electrical device by simply thoroughly washing the T-con board with alcohol, but this was rather a lucky coincidence. Repairs should be taken seriously and the help of professionals should not be neglected.
What to do if the image is missing?
If the TV has lost sound, but there is an image, or you have other similar problems, we recommend following the following algorithm. This is a kind of basic diagnostics that allows you to eliminate the possibility of system failures and roughly identify the cause of the failure. The guide applies to almost all TVs: LG, Samsung, Kivi, Philips, etc.
Method 1: set the correct signal source
If by default (or last time) the first HDMI cable was set as the main signal source, and then you disconnect it, turn off the computer from which the stream is coming, the system may freeze. The TV continues to display an image from it, but since there is no data for processing, the backlight is on, but there is no image on the TV.
How to fix the problem:
- Find the remote control and press the Source button on it.
- Select a different signal source (TV, another connector or desktop). To do this, you either need to press this button several times or use the arrows.
A similar thing can be done from the TV; usually there is a separate button for selecting the signal source or a joystick with access to the main menu.
Method 2: check the quality of the cable connections and their condition
If the TV does not show a picture, it is worth checking whether the cables are well connected. If there is no power indicator, you should check the power supply. What to look for:
- Quality of connection to the TV connector. There should be no play, plus the input should be inserted completely. It is better to clean it of debris, especially if the TV has been lying or transported for some time.
- Visual serviceability of the cord along its entire length. There should be no strong bends, tension, fractures, or cable interruptions that can be felt by your fingers. If there is a block on the cord, the cable on the approach and output should be in good condition.
- Inspect the fork. It must be intact, without severe deformation.
- Check that there is power in the outlet. You just need to connect another device to find out that the problem is not in the outlet.
It is better to carry out similar initial diagnostics with the HDMI cable through which the TV connects to a computer, console, set-top box, etc. Ideally, use another cord, known to be good, if there is one (possibly from a second TV).
Method 3: Increase the volume to maximum
We don’t know the reason, we only have guesses, but this trick has worked for some users: you need to increase the volume to almost the maximum value, and the picture is restored. Then you can return the volume to normal. This indicates some problems in the electrical circuits on the board, but for now you can get by this way.
LCD repair
The first thing to do for diagnosis is to check the source of the signal. This could be a cable box, player, etc. If, when you turn on the TV screen, there is nothing but a uniform white color, you need to press the MENU key on the remote control. You can press this button on the case, if there is one.
If there is a problem with the signal source, the control menu will open on the TV screen. If the device does not react in any way, it means that everything is in order with the set-top box or player, and the fault should be looked for in the equipment itself.
Experts say that in LCDs, in most cases, it is the matrix that is to blame. It rarely breaks just like that; often the breakdown is caused by moisture getting inside the case or mechanical damage. If the part is damaged, a complete replacement is necessary. Unfortunately, it won't be possible to fix it.
Reinstallation of the matrix occurs in stages:
- The body is disassembled.
- The broken matrix is pulled out, and at the same time the technician can fix minor damage in other parts of the electrical device.
- The new matrix is carefully installed in the right place.
- The part is connected to the loop and cable for testing.
- If everything is in order, the body is put back together.
It is important to remember that the matrix is very fragile, so installing it yourself without the appropriate skills is almost impossible. If even after installing a new spare part the equipment does not want to work normally, it is worth looking for the source of the malfunction elsewhere.
Another common cause of a white TV screen is a problem with the voltage supply. This situation can occur, for example, when VON and VOFF are interrupted. As a result, the electronics stop working normally and the screen turns white.
Sometimes the strange behavior of the monitor is due to damage to the electrolytic capacitors, which are located on the main board. In this case, when turned on, the monitor begins to glow with an even whitish light, but the image does not appear.
If there is no picture and the screen glows white, you should additionally check the firmware. If this is indeed the case, the software will need to be replaced.
If there are malfunctions in the work or the equipment has completely stopped functioning, you first need to find out the exact model. It is usually indicated on a small plate on the back cover of the case. This will allow you to choose the ideal firmware. Then you need to go to the official website of the manufacturer, for example, Samsung or LG. There you need to enter the model name and select the “Firmware” tab. The firmware is downloaded from the website, after which you can easily change the software.
Despite its apparent simplicity, you should entrust this issue to professionals. Since there is no image on the TV screen, it will not be possible to reflash it in the standard way through the menu. You will need a special programmer. If you try to change the firmware yourself, there is a high risk of making the wrong step and completely breaking the electronic “brain”.
Sometimes a white TV screen indicates a problem with the microprocessor. Typically, failure occurs due to overheating of the part. The technician first checks the processor for malfunctions, after which you can either replace the textolite or the spare part itself.
A common problem is when the TV plays sound, but the screen does not work.
On repair forums, TV technicians often discuss breakdowns in which the screen does not light up. In this case, the sound and illumination of the TV control buttons can work. Most often, this malfunction is observed on cheap devices of little-known brands.
It is also not uncommon for popular TVs from LG, Samsung, Toshiba and others to be counterfeited. Inexpensive models are equipped with low-quality backlight modules. As a result of using the TV for a short time, the screen goes dark.
And it can only be saved by replacing the diode strip or lighting-related equipment. The tape usually consists of an aluminum sheet with several diodes placed on it (5, 6 or 7 pieces).
The tapes are placed on the substrate at a certain distance from each other so that the light is distributed across the entire screen. If the test determines that one of the diodes has failed, it is replaced with a new one. To quickly fix a breakdown, a cut diode from other tapes is sometimes applied.
But this approach can only temporarily correct the breakdown. Since each tape can have its own specific voltage. When changing this equipment, there is also a need to configure the backlight inverter driver. If one or more diodes fail, dark spots may appear on the screen.
A black screen on the TV when you turn it on, as well as the presence of sound, does not mean that the breakdown may be serious. Before getting to the internal modules of the device, you need to check other possible causes.
CRT TV repair
Such devices are gradually losing popularity, but, nevertheless, requests for their repair come frequently. If a CRT electrical device has no image, and the TV screen glows with a uniform white or green light, the video amplifier is to blame. You can check this by trying to increase or decrease the brightness. If there is no response, the video amplifier board will need to be adjusted. First of all, it is necessary to inspect the capacitors in the microcircuits and, if there is a malfunction, replace them with new ones. In severe cases, the entire video amplifier or picture tube will need to be replaced.
What to do if you couldn’t fix the TV problem?
If simple methods do not solve your problem, the TV is most likely broken. If you are reading this, you are probably not a master. Or a person who understands how a TV works.
In this case, it is recommended to visit a specialist and report under what conditions the device was operating, how long you have been using it and why this could have happened. In cases where lighting parts fail, repairs will be relatively expensive. Often you have to change the entire diode strip.
The owner of the TV can find prices for them on the Internet by adding the name and model to the request. The simplest Chinese diodes are not expensive. But they usually serve relatively little due to their quality.
The technician will have to order parts specifically for your model if he doesn’t have them in stock. This may also take some time. Installation is sometimes accompanied by software configuration, which also increases the cost of services.
Other causes of breakdowns
This category includes mechanical damage and moisture ingress into the housing. The matrix is especially sensitive to such incidents: it breaks down very quickly and will need to be replaced. When calling a technician, be sure to inform him if the equipment has been dropped or water has been spilled on it. This will help you quickly determine the location of the breakdown and make quality repairs.
If the TV is brand new and has been in use for less than a couple of months, there is reason to suspect a manufacturing defect. In this case, you need to contact the store where you purchased the equipment and replace it with a new one under warranty.
Sometimes the glow of a TV screen without a picture is explained by the fact that something inside has broken due to old age. If the device has served faithfully for several years, it is not surprising that the parts inside fail. You can try to repair it, but if the equipment is old enough, it is better to buy a new one.
“Polite Service 5+” accepts requests for repairs of breakdowns of any complexity. Our specialists will repair television equipment of any brand, reflash it, replace used parts and return normal settings. In order not to think about what to do with broken electrical equipment, you just need to call or fill out a form on the website.
Why is there no image on the TV screen?
We will talk about new models of devices with a thin screen and SMART function. After connecting the TV to the network, it can behave as usual - make activation sounds. And also the sound of the TV channel will be heard, while the screen is dark, as if we had not turned it on.
This leads to the conclusion
: the elements of the microcircuit that are responsible for projecting the image onto the screen have failed.
These can be the following parts and modules:
- Power supply
- due to the output of this equipment, the voltage is incorrectly distributed to different parts of the chip. This is a serious TV problem that must be fixed immediately. Otherwise, this threatens the failure of other parts of the Samsung, LG, BBK, etc. TV (you should not carry out repairs if you do not understand what to do); - Backlight inverter
- if the voltage distribution system to the diodes is disrupted, they will not work correctly. This means that they will not be able to illuminate the screen, so it is dark when the TV is working; - Diodes
are the main element of screen backlighting. If one fails, the entire connected line may stop working. In this case, the screen will not be completely dark. And the image is barely visible when the screen is illuminated by an external source (for example, a flashlight).
There are also less serious breakdowns that you can try to solve yourself. This happens due to low voltage from the network. Or other factors affecting the operation of the internal system.
Often, to accurately determine the breakdown, users have to contact a workshop. Since it is quite difficult to determine the reasons when the TV is turned on, but there is no image. Complete diagnostics and fault detection can only be carried out with the appropriate equipment.
This is interesting: is it worth changing the matrix on the TV or buying a new one?
