JVC LT-23E31 BUG, Service Manual

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(No. YA032) 1-5
SECTION 2
SPECIFIC SERVICE INSTRUCTIONS
2.1 DESCRIPTION ABOUT LIQUID CRYSTAL PANEL
2.2.1 STRUCTURE OF LIGUID CRYSTAL PANEL
The Liquid Crystal Panel of this model is TFT Panel. The Print circuit board that consist of TFT array and the print circuit board
adopted stripe shaped image element alignment are used. These two boards are mixed. The Liquid crystal is enclosed between
two boards.
2.1.2 LONG RANGE AFTERIMAGE OF LIQUID CRYSTAL
The small amount of ion material has mixed a liquid crystal panel with the liquid crystal material in the manufacturing process.
If ion material is piled up partially among the poles when the voltage is impressed among the poles, the brightness difference
occurs and becomes a long-range afterimage If same picture is reflected for long time, such a long-range afterimage occurs. If
the long-range afterimage occurs, we recommend that you reflect the single color image or moving picture and so on to restore.
2.1.3 THE DISPLAY REPLYING SPEED OF LIQUID CRYSTAL
Because the speed to display of Liquid crystal panel is slower than the speed of the CRT monitor, some of the moving picture
cannot overtake to the speed to display and the image looks flowing is sometimes displayed. This is not trouble, but efficiency
of Liquid Crystal.
2.1.4 THE EYESIGHT CORNER OF LIQUID CRYSTAL
The liquid crystal panel has the wide eyesight corner for which it is difficult to reverse brightness. The tint changes depending on
the direction to see a screen. This is not trouble, but efficiency of Liquid Crystal.
2.1.5 THE PICTURE ELEMENT FAULT OF LIQUID CRYSTAL
The liquid crystal panel is composed of precise technique but all devices don't always work right.
2.2 ATTENTION ITEMS WHEN REPLACING PARTS
2.2.1 ATTENTION TO EXCHANGE THE LIQUID CRYSTAL PANEL
(1) The stillness electricity sometimes makes damage a liquid crystal panel. In liquid crystal panel exchange, do a measure
of the stillness electricity such as the earth band.
(2) A liquid crystal panel and back-light are made from glass. If you gain an impact to these materials, there is fear to damage.
So in case of treatment, be careful sufficiently.
(3) Fix with the screw after confirming that there is not a float to chassis base when exchanging liquid crystal panel.
After that reflect all the black signals and confirm that brightness leaning doesn't occur near the screw fixation part.
When brightness leaning occurs, slacken a screw in the neighborhood until the brightness leaning is running-out.
(4) Fix the torque that installs a screw below 0.294Nm.
If you install at any more torque, the liquid crystal panel is transformed and sometimes damages.
(5) If you pull out or insert each connector when power is ON, it causes the trouble.
So pull out or insert each connector in the condition to have pulled out a power supply plug.
2.2.2 ATTENTION WHEN EXCHANGING THE FUSE
When exchanging the fuse, please use specified parts. After fuse exchange, confirm that insulater is set to the shield and
insulate surely.