TCL the ML-56 LCD monitor is a flat panel display market TCL Corporation in 2001, its performance is OK, but such displays have a common problem, is used to a year or so, there will sometimes boot image display, or is being used Nikon EN-EL5 Battery Charger when the display suddenly black out occasionally over the last few minutes the image. Performance of the fault is no law, very annoying. I repair process, has encountered more than 10 units of the same fault. If such failure to get to play repair station maintenance, at least $ 300. If you saw below, you will feel this question is too simple, I could get. Actually, this wrong is very small, without having to spend a penny will be able to fix it. If you do not have a tool that takes only a point the money to buy tools.

The working principle of the LCD display: LCD does not light, the appearance of its image and brightness adjustment are dependent on the adjustment of the backlight brightness. Work in liquid crystal display, the backlight lamp emits light through the LCD screen, LCD display image thing that catches the eye of love, then we can see the LCD display of text and images. If the backlight is damaged, there is no light to issue, when we could not see anything. But if we carefully observe the LCD screen, you will see the faint image display on the LCD, then it means that the backlight circuit is broken.

If the backlight circuit is intact, part of the circuit, then we will see the back of the LCD screen bright white light issued. Failures have most of the liquid crystal display backlight circuit or power, the backlight circuit fault most likely is the step-up coil internal short circuit or open circuit.

The tool configuration: ¢ 4 * 200 screwdriver a 20W soldering iron one, solder wire for some children, a knife (these are very easy to find but also very cheap tools).

Maintenance of the whole process:

(1) separately for the liquid crystal display power to observe the failure phenomenon, if the above failure performance. Good signal lines connected to the host, open the display, observe the monitor's power indicator is always green, LCD image display. If carefully to identify whether the faint images appear, but has no backlight.

Desktop clean with a soft cloth pad on the desktop, the monitor and the LCD screen down upside down on the desktop. Must pay attention to the table clean, can not have any debris, otherwise the losses.

(4) Unscrew the four fastening screws, remove the bracket.

Unscrew the display cover screws of the four corners.

Note the location of the two left and right channel audio input lotus plug when removing the back cover, need to pull down, then lift the back cover in order to remove the normal.

The diagram of the metal shield to prevent damage to outside electromagnetic interference on the internal circuit to work. The round hole of over two laps of the cooling holes.

(6) Remove the shield cover the bottom two screws, sliding shield down, and then lift the shield, you can remove.

Note: the two spirals to bear in mind that the installation location, to prevent the screws on the wrong position, causing serious consequences. The screw is too long, it will tighten to wear the LCD screen!

The internal structure of the liquid crystal display consists of four circuit boards, motherboards, audio processing board, backlight high voltage board button control panel.  Panasonic Lumix DMC-ZS3 Battery Charger  Before disassembly, the final hand contact with the water pipe or other grounding device to prevent static electricity from your body to cause damage to the LCD monitor.

8 The following figure is high-pressure liquid crystal display panels, used to produce LCD backlight lamps required 2000V high voltage, the black box is the so-called high tension coil, high tension coil diameter under normal circumstances, very small at high voltage environment, the failure rate is the highest, its accessories, the most difficult to buy.

The components we have to overhaul the inductance coil L1 as shown below. The reason for this failure may be the production process, welding installation, there is no wound inductance coil of enameled paint handling, and direct welding. Because the paint is the insulation material, non-conductive welding points only enameled wire disconnected at one o'clock, so that led to the use for some time, there will be no high-pressure situation, resulting in no image display. . Two pins of the inductor L1 with a knife gently scrape off the insulation paint to expose the Chai red copper layer, the greater the area exposed, welding the more solid, more solid.

10 When the heating of the soldering iron in one hand and solder wire in one hand and iron, the inductance of the two pins welded solid.

Note: Before welding, be sure to remove the high voltage board and control board connection socket (as shown in the red arrow plug location), to prevent the welding, the static electricity generated by the electric iron chip on the motherboard breakdown, resulting in damage.

Welding is completed, a separate power to the LCD screen, and observe the LCD screen display. Screen display, indicating that we have succeeded in troubleshooting.

Note: after power to the LCD screen, do not touch high-voltage plate, to prevent electric shock!

11 according to the anti-open order to monitor installed. Note: The location of the screws must not be installed wrong.

12 power testing machine. Separate power to the monitor, two or three seconds, the display will be images, suggesting that missed a signal line.

13 to monitor the signal line and the host is connected, open the monitor test monitor the work of the normal image display.

At this point, we easily LCD display black screen failure to solve! Do not think that the liquid crystal display of the noble, and we dare not touch it. As long as the bold, but cautious, serious, no we DIYer impossible to do!

Must be careful during maintenance, seriously, every screw in the demolition process must remember that in the paper to its installation position to avoid a mistake.

Postscript: This also makes me think of the beginning of the year saw an article that the CMV CMV LCD monitor, there is no image display at low temperatures, use a JVC BN-VF823 Battery Charger  table lamp it bake for a while will be able to work properly, I estimate the potential but also because a component within the machine Weld, not because their work environment in a 5-35 degrees. Because I am careful examination of multiple LCD monitors are not the circuit board temperature sensing element, in fact, often my mind think about a lot of problems can be solved.

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