Common malfunction and maintenance method of liquid crystal display

Many people do not want to make the LCD screen, feel it fragile, high maintenance risk. Fact

The breakdown of the LCD screen is roughly as follows: screen, Huati, black screen, screen dark, yellow, white blaze, bright line, bright belt, dark lines, black belt, external film scratching.

These faults are relatively easy to repair is the screen aphonia, yellow, white blaze, external film scratching. Screen darkness is actually the tube aging, direct replacement on the line. Yellow and white spots are the problem of backlight, by replacing the corresponding backlight or light guide plate can be resolved. External membrane scratching refers to the surface of the liquid crystal glass of the polarization of the damage, the same manual can be a good replacement. Of course, these can be solved by the replacement of the fault implementation is also a lot of considerations, change the lamp should pay attention to install in place, avoid leaky, processing backlight, should pay attention to dustproof, otherwise the screen light will see the speck of dust; replace the polarizing film to avoid tearing when the screen pressure injury, dust is a big bogey, once in the film covered with dust into , it will produce bubbles, the basic will be scrapped a film to come again.

screen, Huati, black screen are basically due to circuit failure. First of all, should be excluded from the screen, and then see whether the 3.3V has been added to the screen, and then check whether the back level has high voltage and negative pressure output, the main control chip has output. There are quite a number of flower screens because the line driver does not work, simple to fly a few lines can solve the problem. A small portion of the flower screen is damaged by the first piece of the row or column drive module.

The most difficult and most costly maintenance is the maintenance of the cable screen. The causes of these failures are mostly the corresponding driving modules of virtual welding or damage caused, we all know that in the screen glass and PCB board is connected with a number of drive modules. The module is connected to both the PCB board and the glass with extremely fine welding feet one by one. This kind of welding foot is unable to distinguish by the naked eye, also is not we use the brand or the wind gun to be able to weld, must under the high magnification magnifying glass, will weld the foot to use the specialized equipment to carry on the hot pressing. Some of the auxiliary materials used in this process, such as ACF and ACF, are very expensive, and the cleanliness of the operating environment also directly affects the success rate of the repair. This operation machine factor and human experience factor almost each accounted for 50%. But in the hands of an experienced and skilled maintenance engineer, the success rate of repair is basically more than 90%