How to make a clear image on the monitor. What to do if the image on the monitor is unclear. place – does not respond to control buttons

Here are the TOP 10 most common malfunctions of LCD monitors that I have personally experienced. The rating of malfunctions was compiled according to the personal opinion of the author, based on his experience working in a service center. You can take this as a universal repair manual for almost any LCD monitor from Samsung, LG, BENQ, HP, Acer and others. Well, let's go.

I divided the malfunctions of LCD monitors into 10 points, but this does not mean that there are only 10 of them - there are many more of them, including combined and floating ones. Many of the breakdowns of LCD monitors can be repaired with your own hands and at home.

1st place – monitor does not turn on

at all, although the power light may blink. In this case, the monitor lights up for a second and goes out, turns on and turns off immediately. In this case, tugging at the cable, dancing with a tambourine and other pranks do not help. The method of tapping the monitor with a nervous hand usually doesn’t help either, so don’t even try. The reason for this malfunction of LCD monitors is most often the failure of the power supply board, if it is built into the monitor.

Recently, monitors with an external power supply have become fashionable. This is good because the user can simply change the power source in case of breakdown. If there is no external power source, you will have to disassemble the monitor and look for a fault on the board. in most cases it is not difficult, but you need to remember about safety precautions.

Before fixing the poor guy, let him stand for 10 minutes, unplugged. During this time, the high-voltage capacitor will have time to discharge. ATTENTION! It is DANGEROUS TO LIFE if the PWM transistor also burns out! In this case, the high-voltage capacitor will not discharge in an acceptable time.

Therefore, EVERYONE check the voltage on it before repairing! If dangerous voltage remains, then you need to discharge the capacitor manually through an insulated one of about 10 kOhm for 10 seconds. If you suddenly decide to short-circuit the leads, then protect your eyes from sparks!

Next, we proceed to inspect the monitor’s power supply board and replace all burnt parts - these are usually swollen capacitors, blown fuses, transistors and other elements. It is also MANDATORY to solder the board or at least inspect the soldering under a microscope for microcracks.

From my own experience I will say that if the monitor is more than 2 years old, then 90% there will be microcracks in the soldering, especially for LG, BenQ, Acer and Samsung monitors. The cheaper the monitor, the worse it is made at the factory. To the extent that the active flux is not washed away - which leads to failure of the monitor after a year or two. Yes, yes, just when the warranty ends.

2nd place - the image blinks or goes out

when you turn on the monitor. This miracle directly indicates to us that the power supply is faulty.

Of course, the first thing you need to do is check the power and signal cables - they must be securely fastened in the connectors. A flickering image on the monitor tells us that the monitor's backlight voltage source is constantly jumping out of operating mode.

3rd place - turns off spontaneously

after the time has elapsed or does not turn on immediately. In this case, again, there are three common malfunctions of LCD monitors in order of frequency of occurrence - swollen electrolytes, microcracks in the board, faulty microcircuit.

With this malfunction, a high-frequency squeak from the backlight transformer can also be heard. It typically operates at frequencies between 30 and 150 kHz. If its operating mode is disrupted, vibrations can occur in the audible frequency range.

4th place - no backlight,

but the image is viewed under bright light. This immediately tells us that LCD monitors are faulty in terms of backlighting. In terms of frequency of occurrence, it could be placed in third place, but it is already taken.

There are two options - either the power supply and inverter board burned out, or the backlight lamps are faulty. The last reason is not common in modern monitors. If the LEDs in the backlight fail, then only in groups.

In this case, the image may darken in places at the edges of the monitor. It is better to start repairs by diagnosing the power supply and inverter. The inverter is that part of the board that is responsible for generating a high-voltage voltage of about 1000 Volts to power the lamps, so under no circumstances should you try to repair the monitor under voltage. You can read about it on my blog.

Most monitors are similar in design, so there shouldn't be any problems. At one time, monitors simply fell off due to poor contact near the tip of the backlight. This can be cured by carefully disassembling the matrix in order to get to the end of the lamp and solder the high-voltage wiring.

A simpler way out of this unpleasant situation can be found if your friend-brother-matchmaker has the same monitor lying around, but with faulty electronics. It won’t be difficult to make two monitors of similar series and the same diagonal.

Sometimes even the power supply from a monitor with a larger diagonal can be adapted for a monitor with a smaller diagonal, but such experiments are risky and I do not recommend starting a fire at home. But in someone else’s villa, that’s a different matter...

6th place - spots or horizontal stripes

Their presence means that the day before you or your relatives had a fight with the monitor over something outrageous.

Unfortunately, household LCD monitors are not equipped with shockproof coatings and anyone can offend the weak. Yes, any decent poke with a sharp or blunt object will make you regret it.

Even if there is a small trace or even one broken pixel left, the stain will still begin to grow over time under the influence of temperature and voltage applied to the liquid crystals. Unfortunately, it is not possible to restore dead monitor pixels.

7th place - no image, but backlight is present

That is, a white or gray screen appears on your face. First, you should check the cables and try connecting the monitor to another video source. Also check whether the monitor menu is displayed on the screen.

If everything remains the same, look carefully at the power supply board. The power supply of an LCD monitor usually generates voltages of 24, 12, 5, 3.3 and 2.5 Volts. You need to use a voltmeter to check if everything is okay with them.

If everything is in order, then carefully look at the video signal processing board - it is usually smaller than the power supply board. It contains a microcontroller and auxiliary elements. You need to check if they are getting food. Touch the contact of the common wire with one (usually along the outline of the board), and with the other, walk along the pins of the microcircuits. Usually the food is somewhere in the corner.

If everything is in order regarding the power supply, but there is no oscilloscope, then we check all the monitor cables. On their contacts. If you find something, clean it with isopropyl alcohol. In extreme cases, you can clean it with a needle or scalpel. Also check the board with the monitor control buttons.

If all else fails, then perhaps you are faced with a case of broken firmware or microcontroller failure. This usually happens from surges in the 220 V network or simply from aging of the elements. Usually in such cases you have to study special forums, but it’s easier to use them for spare parts, especially if you know a familiar karateka who fights against unwanted LCD monitors.

8th place – does not respond to control buttons

This case can be easily treated - you need to remove the frame or back cover of the monitor and pull out the board. Most often there you will see a crack in the board or in the solder.

Sometimes there are faulty or . A crack in the board violates the integrity of the conductors, so they need to be cleaned and soldered, and the board must be glued to strengthen the structure.

9th place - reduced monitor brightness

This occurs due to aging of the backlight bulbs. LED backlighting, according to my data, does not suffer from this. It is also possible that the parameters of the inverter may deteriorate, again due to the aging of the components.

10th place - noise, moire and image jitter

This often happens due to a bad VGA cable without an EMI suppressor -. If replacing the cable does not help, then it is possible that power interference has penetrated into the imaging circuits.

Usually they are eliminated from the circuit design by using filter capacitors for power supply on the signal board. Try replacing them and write to me about the result.

This concludes my wonderful rating of the TOP 10 most common malfunctions of LCD monitors. The bulk of data on breakdowns was collected based on repairs of such popular monitors as Samsung, LG, BENQ, Acer, ViewSonic and Hewlett-Packard.

This rating, it seems to me, is also valid for and. What is your situation on the LCD monitor repair front? Write to and in the comments.

Sincerely, Master Pike.

P.S.: How to disassemble the monitor and TV (how to snap off the frame)

The most common questions when disassembling LCD monitors and TVs are how to remove the frame? How to release the latches? How to remove the plastic case? etc.

One of the craftsmen made a good animation explaining how to remove the latches from engagement with the body, so I’ll leave it here - it will come in handy.

To view animation— click on the image.

Question from a user

Hello.

I have a fairly old computer (8-10 years old, I took it from my own hands specifically for the dacha). I recently reinstalled Windows on it and the screen started flickering a lot. The eyes get tired quickly, especially against a white background (very noticeable).

How can I stop this blinking?

PS I completely rummaged through the disk from the previous owner with drivers and installed everything that was on it. Didn't help...

Good day!

In general, both very expensive monitors and cheap ones can flicker. (both old and new). And many users are very mistaken, thinking that such monitor shortcomings are a thing of the past. In fact, your eye may not see the flicker, but it will (for example, you can indirectly notice this by how quickly your eyes get tired)! Below I will show examples.

As for the author of the question, the reason for the flickering, judging by his description, is associated with the low refresh rate of the screen (this is especially true on older PCs that use CRT monitors (these are so “thick”, see on the right in the preview picture)). As a rule, to fix this problem, you need to install the appropriate drivers for the monitor and video card, and then configure them correctly.

In the article I will analyze these and other reasons in more detail. So...

By the way, I want to add here... If, among other things, you have ripples on your screen, vertical and horizontal stripes are running, distorting the image (as in the example below), then you better read this article first: . In it I pointed out the main reasons for this “behavior” of the monitor/PC...

By the way, there is a very good way, find out if your screen flickers (flashes) a lot. Most modern smartphones are equipped with a camera: so, turn on the camera and just focus it on the screen (no need to take photos, just look). It will clearly show whether your monitor is flickering.

As a rule, if something is wrong, you will see vertical/horizontal stripes running on your smartphone (usually from top to bottom (from left to right)). This is the very flickering we are talking about. See example below.

Monitor 1 and Monitor 2 - note the stripes on the second (phone test)

A few words about modern and CRT monitors

Modern monitors, as mentioned above, can also flicker (even if you just brought it from the store, and just at a glance it’s not noticeable). To see if these stripes exist, use your smartphone’s camera or a regular pencil (you need to quickly wave it in front of the screen and see how its silhouette will be displayed (see example below)).

This may happen due to the way the monitor backlight works. (this is not a defect, and you cannot return the monitor for this reason! To protect yourself from such models, you need to test the device with your own eyes in a store). Typically, this feature appears when brightness is reduced!

Those. the monitor can work perfectly at 80% brightness, but if you try to set it to 40%, you will see (on a smartphone) how the screen starts to flicker (and in my opinion, this is not good).

As a rule, better monitors (in this aspect) use eye protection technologies (Flicker Free, SoftBlue, SmartImage, etc.).

But, I personally came to the conclusion that this does not provide a 100% guarantee. And the best way out is to check the operation of the monitor when purchasing – i.e. ask the seller to turn down the brightness, open a blank white sheet and point the camera (or buy something specific that you have already looked at reviews and tests on).

If you already have a flickering monitor, then you can try to fix the problem like this: increase the brightness (just be careful here too), and increase update rate (if possible). Usually, if you reduce the screen resolution, you can increase the refresh rate.

As for CRT monitors, then at a frequency below 85Hz screen refresh– it is highly not recommended to work ()! On newer LCD monitors, operation at 60 Hz is also allowed (since the principle of their operation is different).

But I note that, nevertheless, if your monitor is capable of operating at a higher frequency, it is recommended to set it. Below I will show you how to find out the current frequency and how to change it...

Setting the screen refresh rate

Method #1

Press a combination of buttons Win+R, a small window should appear "Run". In the "Open" line enter the command desk.cpl and press Enter.

Next you should open the display settings: depending on the version of Windows you are using, the settings screen may vary slightly. For example, in Windows 10 you need to open the "Graphics Adapter Properties" link.

In the "Monitor" subsection there should be a "Screen refresh rate" tab. Actually, you click on it and change the frequencies to the highest that your monitor supports.

Important point!

If you do not have drivers installed for your monitor or video adapter, then you will almost certainly not be able to set any modes other than 60 Hz (even if your monitor supports them!). In this regard, I recommend using special ones (they will automatically check all your equipment and update everything that is necessary).

Method #2

If you have drivers for the video adapter, then just right-click on any free space on the desktop, and then select their settings in the context menu that appears (in my case, it’s “Intel Graphics Settings”).

As a rule, in the main section you can specify the refresh rate, resolution, adjust brightness, scaling and other parameters.

About drivers

If you installed all the drivers from the disk (which came with your PC), then it is far from a fact that all of them were installed correctly in the system. Often, after changing the Windows OS, old drivers, even if they can be installed, do not work correctly...

To check if you have a video driver on your system, open device Manager (to do this, use the combination Win+R, then the command devmgmt.msc ).

In Device Manager, open two tabs: “Video adapters” and “Other devices”.

If you have a video driver installed, then in the “Video Adapters” tab you should see the name of your video card (without exclamation marks).

If there is nothing in the "Video adapters" tab, or it says "Standard VGA video adapter" (or "VGA compatible video controller") - then there is no driver on your system. An example is shown in the screenshot below.

In general, I have a “big” article on my blog dedicated to updating the video driver. I recommend checking it out if you have a problem with this.

ADDITION!

By the way, after installing modern Windows 10, you may encounter that the driver will be in your system (i.e. Device Manager will show you that everything is "OK") , but you won’t find links to their control panel. In this case, you also need to reinstall the driver by downloading it from the official website (see link to instructions above).

About cables and cords

The problem with the picture flickering on the monitor screen may be due to cable damage. Often, by the way, when it is damaged by pets...

By the way, it is very advisable to fix the cable (at least with tape (the ideal option is special clamps, see photo below)) so that it does not “dangle” in a slight draft, when someone passes by, or you sit at a computer desk...

About a malfunction of the monitor, video card

I also cannot help but note that distortion of the picture on the screen often signals hardware faults (i.e. there is a problem in the hardware). Diagnosing for sure which one is not always easy...

First, I recommend connecting your computer (laptop) to another monitor; and the current monitor - to another PC. This way you can immediately find out where to look for the cause of blinking on the screen: in the system unit or in the monitor (sorry for the tautology).

As an extra!

How to connect a monitor to a laptop -

As for the video card, to check it you can use special utilities that can conduct a stability test. You can find out how to do it from the article below.

Checking the video card for performance, reliability and stability test -

I know that many people do not pay attention to the various flickering and distortions on the screen. However, this is purely my opinion – this should not be ignored! The fact is that a low-quality picture on the monitor not only spoils the impression and emotions (God bless them), but also affects our vision! , tense up, start to tear up, etc. None of us really need unnecessary health problems...

For any LSD (liquid crystal) monitor, there is only one resolution at which the display can function normally. In some cases, the problem of loss of image sharpness can be solved simply by correctly setting the required resolution.

More information about the services can be found on the website http://technari.com.ua/ru/services/for-home/notebooks/cable-replacement/. If the cable breaks, images may deteriorate, colors may be distorted, and other problems may occur.

In Windows XP, to set this parameter you need to follow a series of sequential steps:

1. Go to the “Control Panel” and in this window click on the “Display Properties” option.

2. In the window that opens, mark the required resolution value recommended by the display manufacturer.

In Windows Vista AND Windows 7, the following simple steps are enough:

1. Right-click on a free part of the desktop and select the “Screen resolution” option from the context menu that appears.

2. As a result, a window called “Screen Settings” pops up. In it you need to find the line “Resolution” and click on the arrow next to this name with the mouse.

3. A list of possible screen resolutions appears, among which you need to find the line next to which it says “Recommended”. This value will satisfy all the requirements of the installed operating system.

Sharpness adjustment

Windows Vista and Windows 7 allow you to quickly and efficiently adjust the sharpness of the information displayed on your screen, in the form of text or web pages. To do this, perform the following manipulations:

1. Go to the “Control Panel” and use the mouse to call up the “Screen” window.

2. In the window that appears on the left, select the “Clear Type” tab

3. After that, in a new window, mark the monitor to be configured (if there are several of them) and continue to move on.

4. In the windows that open, select the text you like from the point of view of reading comfort.

After testing is completed, a special program will set custom sharpness values. Sharpness can also be set in the monitor menu. Operating the control buttons, mark the “Clarity” option and find its acceptable level.

It is advisable to start any display settings by installing the required drivers and the recommended resolution. By manipulating the monitor panel buttons, you can manually adjust the brightness and RGB color balance.

Friends, let's talk about an equally important topic - the ease of using a computer, namely the clarity of the fonts displayed on the monitor.

Many of us work at the computer all day long. And of course they know how tired the eyes are. But do many of us do special exercises every day to relax our eyes? I think not.

Let's help our health at least a little and determine the necessary clarity of fonts.

Microsoft has already thought about our eyes and is offering us its technology ClearType. This technology is designed specifically for LCD monitors and provides font smoothing, thereby improving readability. ClearType displays words on your monitor screen as crisp and clear as if they were printed on a piece of paper.

Now let's adjust the clarity of the fonts

1. Go to the menu “ Start”, then to the section “ Control Panel”, then select “ Design and personalization” (you can use windows search for other operating systems, see below)

2. In the window that opens, find the section “ Fonts” and click on the link below “ Setting ClearType Text" A new window will open.

On Windows 10 it will be located in the same section.

3. Check the box “ Enable ClearType”, click on the button below “ Next" A new window will ask you to set the optimal screen resolution. After making the appropriate settings, press “ Next”.
4. You will be asked to select the best option for displaying text in 4 examples. After making the appropriate settings, click the “Finish” button.

Setting the font size

If you feel that the font displayed in applications is too small, and you are constantly straining to read something on the screen, then you simply need to increase the default font size.

To do this, go again to “ Control Panel” –> “Design and personalization” –> click on the item “ Fonts” –> then on the right side of the control window select “ Changing the font size” and select the most convenient option.

And now we are happy with the result. Our eyes will definitely thank us now.