Monitor - a device that displays the result of the processes occurring in the computer. For many users, this is perhaps the most important component of the computer. The monitor breaks, as a rule, relatively rarely, most often because this mechanism has simply exhausted its resource and it's time to choose a new device. Consider the most typical monitor malfunctions and methods for their elimination.
Programs for testing and setting up monitors
Are you having display problems on your computer monitor? Here are some common monitor problems. Follow these instructions to fix monitor display? There is no display on the monitor. . Problem: There is no display on the monitor at all, not even an error message. This is usually a physical connection issue, power issue, or data cable issue. If the steps below don't work, you may need to replace your monitor or take it to a tech store for repairs.
If the monitor does not turn on, then first of all you need to check whether it is connected to the mains, make sure that the electrical cable is working, and there is voltage in the outlet.
Sometimes during the operation of a CRT monitor, a characteristic high-frequency squeak is heard. It is barely audible, but at the same time it can cause severe irritation to users. This phenomenon often occurs when changing monitor modes. Note that after prolonged use, this sound may fade and eventually disappear completely. This usually happens when the monitor is operating at its maximum refresh rate at its maximum screen resolution. To fix a problem, sometimes it is enough to reduce the screen refresh rate.
Make sure the monitor is connected to a power source and the monitor power button is turned on. For other issues, it's best to connect to another computer and see if it works. If you have multiple monitors connected for a dual-screen display, set it to display on a single monitor. Check if both monitors are working. Gently pull on the cord to make sure the plugs are secure. If none of the above work, plug in a working monitor for final confirmation.
- If there is no power, you may need to check the power cable.
- Make sure it is physically connected correctly.
- Sometimes flickering of the monitor and video.
Often users of CRT monitors complain about the lack of image clarity. If this is an old monitor, then in all likelihood it has simply worn out its resource and needs to be replaced. It also happens that the monitor, due to design and other features, cannot support operation in this mode with the current parameters. Sometimes you can solve the problem by reducing the screen resolution or refresh rate.
Programs for Microsoft Windows
If not corrected soon, this serious problem with health, as it creates problems with the eyes, headache, exhaustion from stress, etc. Then select the "Monitor" tab and select a different speed from the "Screen Refresh Rate" drop-down box. The video light is too dark or bright. . Problem. The video is too dark or bright on the monitor. The root cause of this issue is that someone is toggling the settings and changing the optimal settings.
Some monitors have Brightness or Contrast buttons that can be easily adjusted when moving or cleaning the monitor. The images on the screen do not match the screen size. . Sometimes it may be possible to select a resolution that is not compatible with your monitor. From the drop-down list, select a resolution that matches the monitor's native resolution. You can see a dot on the monitor that looks stuck. The dot is too bright or too dark. If this spot shows some color, it may be a stuck pixel.
Another common monitor malfunction is that it glows (that is, it works), but the image is not reproduced on it. main reason such a malfunction is the absence of a signal at the output of the video card. Check the video cord is working, try replacing the video card.
In CRT monitors, there is also such a problem as a dim image, due to which it is sometimes almost impossible to work. To eliminate this trouble, you can use the monitor settings that adjust the clarity and brightness. If this does not help, then you will have to change the monitor. Such malfunctions indicate the development of the kinescope of its resources, and it is impossible to repair it.
These problems are potentially solvable. If that doesn't work, you may need to have it repaired or replaced by the manufacturer. Use narrow-ended objections such as a pen, a pencil with rounded edges. You can also use a clean microfiber or paper towel to press on the problem area. Don't push too hard, hard enough to find white glow at the point of contact. This device can be used to fix dead or stuck pixels.
- Use a dark or white background on the screen to highlight the space.
- Push it a little harder each time.
Sometimes the monitor displays an obviously unadjusted image. In particular, application windows and other interface elements are too large, and they can be disproportionate, which means that the screen resolution is clearly lost. In this case, the problem is most likely in the monitor or video card drivers (by the way, this often happens as a result of a complete reinstallation operating system, after which, as you know, you often need to install some drivers).
Computer monitors are quite simple, used if not in real design: plug them in, turn them on, look at your computer on a bright part. Unfortunately, much of this material requires either a certified repair or a complete replacement to fix it. If you're particularly comfortable with electronics and just have access to cheap replacement parts, it's usually best to either return the monitor to the manufacturer or just buy a new one.
The principle of construction and the main types of malfunctions of LCD monitors and the method of their repair
If your monitor screen is flickering or stuttering frequently, there are several different problems that you may have encountered. It could be something as simple as a loose or broken video cable. Therefore, first tighten the cable on both the monitor and the computer, or simply replace the cable. The same goes for the power cable: make sure it is protected at both ends, and if the problem persists, replace it if possible.
Monitor problems
If, when the monitor is turned on, the LED on its panel does not light up - the power indicator - most likely, the monitor's power supply has failed. But before you make a final “verdict” on him, check network cable and the presence of voltage in the network.
The most common source of monitor malfunction is: poor-quality power, aging of elements as a result of operation, violation temperature conditions, mechanical damage and liquid ingress into the housing. If liquid gets inside the monitor, you must immediately turn it off and dry it properly. Do not rush to turn it on, it is better to wait a bit than to ruin the equipment.
An incorrect refresh rate setting can also cause flickering. The refresh rate is the number of times a computer sends an image to the monitor per second, expressed in hertz. Go to your operating system's display settings to make sure the correct hertz setting is set - you may also need to update your video drivers.
Unfortunately, most of the other flickering symptoms are caused by a power shortage somewhere in the monitor itself. You might be consuming too much energy from electrical circuits your home or overload your surge protector - just move the power adapter to a different slot to check it out. But it's more likely that there is a loose or defective component in the screen assembly. If so, repair or replacement are the answers.
Power surges sometimes occur in the mains, which adversely affect the performance of the monitor's power supply and can lead to its failure. Often, the repair of monitors is not limited to the repair of the power supply. Image distortion, extraneous sounds during operation, overheating may occur.
There is not much for a dead pixel, it is a physical failure of the screen bezel. Luckily, one or two dead pixels usually don't mean you have to throw away the entire monitor; maybe bypass it or ignore it. You can also look into a warranty replacement, although many monitor manufacturers won't replace the screen until a few pixels are gone.
The stuck pixel may be different. Depending on how the problem manifests itself, it is possible to return the pixel to working mode. For this there are various methods, ranging from physically "massaging" the screenbar itself to running programs that quickly cycle part of the screen through the color spectrum. You can try some of these solutions, but as a warning, in my personal experience, it is extremely rare to find a durable solution for a stuck pixel.
If the monitor exhibits interference (distortion, shaking, dark edges, etc.), the cause is either a software problem or a defective monitor (video card).
Run several different programs that perform the same function. If the problem appears only in one of them, for example, when watching a movie, the reason is in the program itself. If not, the problem is in the hardware. If the problem is in the program, check the settings and change the codecs.
There's nothing you can do here: even if your monitor is within the warranty period, it almost certainly won't cover physical damage. The most common problem that can cause hum or buzz noise on a monitor is a backlight problem, usually with compact fluorescent lamps used for lighting in older models. Buzzing can occur due to problems with power regulation for one or more light bulbs. Try adjusting the screen brightness up or down to see if the noise dissipates; of course, this may be a less than optimal solution if you need screen brightness at certain settings.
Problems can arise due to voltage fluctuations in the network. Perhaps when you turn on several electrical appliances that consume a lot of energy at once. Try connecting your PC to a different outlet. Pay attention to the integrity of the power cord, check for kinks, creases. If the voltage drops do not stop, install a high-quality surge protector, voltage stabilizer.
If your monitor is out of warranty, take it to your local electronics store - they will probably exchange the part for significantly less than the cost of a new screen. If your screen unexpectedly shows the wrong resolution for your desktop, which is indeed the most likely culprit for your graphics card. It is likely that the problem is either a software component or the graphics card itself. Usually, a driver update will usually fix this issue, although a new graphics card might be fine.
Interference can be caused by powerful radio or electrical equipment. It is necessary to move such devices to a sufficient distance from the monitor or shield it.
CRT monitors become magnetized over time, which leads to interference, distortion. If the monitor is magnetized by a single impact, it is necessary to turn it on and off several times in a row, the built-in demagnetization system will cope. If the problem persists, purchase a special degaussing coil. The "folk" way - with the included electric razor, swipe around the perimeter of the monitor, sometimes it helps.
If the problem persists even if you test the monitor on a different computer, there may be something wrong with the internal electronics. Try an alternate login if possible. A monitor that turns off intermittently may not be getting enough power from a wall outlet or surge protector - check your home's breaker again and make sure the power cord is connected properly. It is also possible that the internal or external power converter is overheating. Carefully check the case of the monitor itself or the power adapter; if they are too hot to touch for more than a few seconds, they must be replaced.
The presence of "broken" pixels - constantly glowing or shaded dots - can only be "cured" by replacing the matrix, which is not always justified from a financial point of view.
Sometimes the cause of the defect may be suboptimal monitor settings. It is worth being especially careful if there are small children in the house, they are very fond of “pushing” the buttons. Some pets love to gnaw on cables, for example, once a pet cat gnawed the cable connecting the system unit to the monitor. As a result, the color rendition was disturbed.
This suggests that the additional expense of a laptop over a monitor could make it a much better candidate for a repair rather than a replacement. At the very least, it's probably worth diagnosing and quoting at a repair shop if you're not comfortable replacing the screen assembly yourself.
Messages appear on the monitor when the computer starts, shuts down, or enters sleep mode. Some of the messages that may appear. These messages are normal when the computer actually goes to sleep or loses video. However, one of these messages appears when the team is supposed to show a video, something is happening.
Periodically, it is desirable to carry out maintenance of monitors - disassemble, clean from dust and solder critical areas, if necessary.
Typically, monitor repair consists in replacing or repairing a faulty PSU, control board, replacing a microcircuit, transistor, fuse, connectors.
Often, the inoperability of an LCD monitor is caused by a PSU malfunction, which is quite possible to fix at home. Careful troubleshooting will allow you to successfully repair or at least pinpoint the components that need to be replaced.
If you suspect that the monitor should display an image of the computer instead of a message, use one of the following sections, depending on how the monitor behaves after the computer is turned on. Most likely, the computer went into sleep mode. To wake up your computer from standby mode, follow these steps:
If you are unable to reactivate your monitor, you may need to connect your computer to a different monitor in order to complete the following steps. After completing these steps, connect your hardware to your original monitor. If the hardware still does not wake up, press the power button on the computer case for one second and release it. If the monitor does not turn on again, restart your computer and turn off suspend mode: NOTE: Disabling sleep mode does not solve the problem, but it will help determine if the problem is related to the suspend mode or otherwise suspend the thing. Use the computer with the power settings turned off to determine if the message continues to appear. Most likely, the command will not return from a suspended state. If the message continues to appear, the problem is with the software. What to look for: If the message appears after opening the software, such as when starting a game, the software forces the screen resolution to change to a mode not supported by the computer and monitor. Do not use this software or change video settings. If a message appears after the command has been idle for some time, the screen saver is most likely the cause of the problem. Turn off the screen saver to see if the problem is gone.
- Move the mouse or press the space bar.
- If the device does not activate again, press the button on the keyboard.
- You may need to double-tap the Hanging Keyboard button.
In work, try not to rush, so as not to confuse the outputs, as well as the PSU itself, which is connected to the monitor.
Increased voltage of the secondary power leads to damage to the power board or the processor board of the LCD monitor, the switching unit (it depends on the device of the monitor, the voltage may come to different units).
In any case, only diagnostics will reveal the malfunction. In most cases, all parts are available and faults can be fixed. Preliminary diagnostics will allow you to identify possible damage, identify faulty elements, eliminate repeated failures and the occurrence of interference when turning on the power source after repair.
Determine the type of PSU, the power converter construction scheme, the circuit design and the purpose of the PSU circuits, then the element base, the type of microcircuits and transistors used.
Both internal and external PSU are used. The first is located in the monitor case. This is a switching converter that transfers AC mains voltage to multiple output DC power rails. The disadvantage of the built-in PSU is the presence of a powerful high-voltage pulse converter inside, which negatively affects the operation of the monitor.
An external PSU is a network adapter made as a separate conversion module AC voltage networks in constant pressure. Both are made according to the scheme of a pulse converter. An external PSU eliminates the power stage from the monitor, increasing reliability.
Both options usually form +3.3 V, +5 V, +12 V, +3.3 V at the bus output to power digital microcircuits; +5 V for standby voltage and power supply of digital, analog circuits, LCD panels, etc.; +12 V - to power the backlight inverter and LCD panels.
In an external PSU, all voltages are generated from a single 12–24 V input bus using DC-DC converters to D.C.. The conversion is carried out by a linear or pulse regulator. The former are used in low-current circuits, and pulse converters in those channels where the current reaches significant values. The DC-DC converter is almost always located on the monitor's main control board.
The circuitry of the converters is the same type, the difference in the number of output buses at the output and element base. The converters are made on the basis of pulse step-down voltage converters, they include a multi-channel PWM chip that controls the output power signal in a cascade.
Adjustment and stabilization of the output buses is performed using PWM technology in feedback circuits.
Visual inspection of parts and condition printed circuit board will reveal external defects of elements. The faults of the fuse, varistor, thermistor, resistors, transistors, capacitors, chokes and transformers are determined.
A blown fuse in a glass case is not difficult to determine - a burnt wire, plaque on the glass, glass damage. The fuse current is approximately 3A. Replacing it with a fuse with a high current will damage other elements of the PSU or the LCD monitor itself.
Varistors, thermistors, capacitors in the input circuits of the power supply unit often have mechanical damage when they fail. They turn out to be split, cracks are visible, the coating flies around, soot on the case. Defective electrolytic capacitors "swell" or have damage to the case, in which electrolyte can be splashed onto adjacent radio components. When the resistors burn out, the color of the case changes, traces of soot may appear. Sometimes cracks and chips appear on the resistor case.
Pay attention to violations of the integrity of the case, color changes of elements, traces of soot, the presence of foreign objects, the slightest damage to printed conductors and places with suspicious soldering quality.
If the fuse is blown, be sure to check the rectifier bridge diodes, thermistor, varistor, output filter capacitor, switching transistor, current resistor. So you will identify a short circuit at the input of the PSU, if it is present. Be sure to check the control chip (PWM controller).
Be careful when choosing a replacement for powerful key transistors and elements of the secondary output stages (diodes, capacitors, chokes). Install a powerful key transistor (or a powerful hybrid microcircuit) on a radiator carefully. The case of a power transistor is usually connected together with its collector (drain), so it must be isolated from the heatsink. For insulation between the installed radiator and the transistor case, mica gaskets are inserted, special heat-conducting rubber, and if the case is completely plastic, then only heat-conducting paste is used. After installing and soldering the transistor, make sure that its collector (drain) does not come into contact with the radiator.
A trial run of the PSU is performed with a load. Instead of a monitor, it can be loaded with equivalent external circuits, such as a +12V and +24V 10-60W light bulb. To measure voltages, it is advisable to connect a voltmeter to the PSU output before turning it on.
At the testing stage before turning on, you can also put a 220 V light bulb with a power of 100-150 W instead of a mains fuse, it will give a visual representation of the current consumed by the source as a whole. If the lamp glows strongly when the power supply is turned on, the power consumption is high and a short circuit is possible in the primary circuit of the power supply, with normal current consumption, the lamp glows dimly. This method is a safety violation, so be careful.
At the time of switching on, it is necessary to observe all safety measures, observe the operation of the PSU in goggles, since when turned on, electrolytic capacitors may fail. During the initial power-up and operation of the PSU, pay attention to the appearance of possible sounds (whistling, clicks). The appearance of smoke, the smell of burning will indicate an unresolved problem and the presence of a malfunction. Sparks and flashes, as a rule, are observed when fuses, power switches and diodes fail.
Provide the ability to quickly turn off the power supply of the 220 V power supply from the PSU.
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