Repair of monitors

The result of the fruitful cooperation of a large number of physicists, engineers and technologists, as well as the receipt of special materials as a result of long research in the chemical industry, are all kinds of information display devices, presented, for example, in the form of a monitor matrix. Built using various technologies, monitor displays have come a long way from the most primitive (but no less technically complex) LCD with a resolution of 320 by 240 and a diagonal of just a couple of inches, to OLED panels with a size of almost 50 "and a resolution of 3840 × 2160 and more.

Matrices used in monitors:

  1. LCD - displays built using liquid crystals. The most numerous group, which includes TN + Film, IPS and various *VA matrices.
  2. OLED is a promising technology that allows the production of ultra-thin and even flexible displays based on organic light-emitting diodes, obtaining black color unattainable by other types of matrices, displaying a bright and rich picture, but due to the imperfection of the materials used, it has significant drawbacks in the form of an early "fading" , as well as "burn-in", which manifests itself as a phantom afterimage after working with a static picture for a long time.

Do not confuse OLED matrices with LED backlighting: the first is able to emit light on its own and does not need backlighting, and the second only uses LEDs instead of the previously used CCFL lamps to illuminate LCD matrices.

The need to repair the monitor arises in the following cases:

  1. Mechanical damage to the matrix when the monitor falls or accidentally hits the matrix with objects common in everyday life.
  2. The monitor's power supply has failed.
  3. Malfunction of the "scaler" - a board responsible for converting the input signal coming via the analog VGA interface or digital DVI / HDMI / DisplayPort into commands understandable to the control electronics of the matrix, turning individual pixels on and off, thus forming an image.

Unfortunately, due to its design, the repair of a broken monitor matrix consists only in replacing it with a new one with similar parameters - it cannot be restored. But with careful use of the monitor and the exclusion of mechanical influences, the matrix, which is based on liquid crystals, will serve you for a long time, since the components used in it have the highest possible reliability.
When it comes to electronics, power supplies are the most frequently broken elements in monitors. And here, most often, the reason lies in swollen or dried electrolytic capacitors, due to their overheating, when the manufacturer uses unsuitable components in order to reduce the cost of production, as well as exceeding their operating voltage. In addition, the monitor's power supply may require repair if there is a surge in mains voltage, when it rises from standard 220V to 300 or more volts, damaging the input high-voltage circuits of the pulse converter.

In modern monitors, the use of a power supply located outside the monitor, when it is connected in the same way as a PSU is connected to a laptop, has become widespread, and at the same time significantly reduces the thickness of the monitor, making it outwardly more attractive to a potential buyer. It also simplifies the repair of this element, since it is not necessary to disassemble the monitor case.
Another reason for the failure of the computer monitor may be the failure of the scaler board, while the power indicator works, but the monitor does not show an image and is not detected by the operating system.

The backlight may also disappear on some monitors - this often happened in the past when fluorescent lamps (CCFL) were used instead of LEDs. Plus, the inverter (voltage converter), in particular, the high-voltage transformer, was subject to frequent breakdowns. This problem has now faded away due to the ubiquitous transition of monitors to the use of light-emitting diode (LED) backlighting, which lasts much longer and causes less hassle.

Your monitor needs to be repaired if you experience the following symptoms:

  1. The monitor does not turn on and the power indicator is off. 
  2. When turned on, the monitor does not respond, but the indicator blinks (on).
  3. The highlight fades in and out.
  4. The backlight does not turn on.
  5. The image is flickering.
  6. Vertical stripes appear on the screen.
  7. No image, backlight is working (the screen is completely white);
  8. The brightness of the image has decreased or when the native resolution of the matrix is ​​\u200b\u200bset, it is blurry.

Repair of the monitor should be entrusted to qualified service center employees who have experience in selecting the necessary spare parts and working with electrical circuits under high mains voltage.