Today, I received a 32-inch LCD TV Konka. The fault manifests itself as a cold boot protection without backlight and sound. The second boot can sometimes be turned on normally, sometimes not. Talk to the user about the price and change the integrated power board (34006601). After bargaining, the user decides to repair the board.
Start disassembling, measuring the normal voltage, is it disturbed to make the backlight not bright? Later, I saw a similar model and the same common problem on the forum. Try to short the R773 resistor, the boot fault still exists, and it won't work. Also try C756. Increase the capacity, the test machine is still not working, the fault is not lifted, and the aluminum foil is attached to the back of the logic board. The above three have not solved the fault. Is it necessary to change the power supply integrated board? Also ruled out the virtual welding, I am disheartened!
After two hours, the boot unintentionally found that the backlight flashed a few times before booting or no backlight. Look at this screen is a plastic screen, is the aluminum foil inside broken? It is also possible to think about it, because it has also repaired a similar failure of Hisense LCD TV.
I started to dismantle the screen. After the dismantling, I broke a lot of articles. A total of 10 broken 6 pieces. I decided to put the aluminum foil on it and added a vertical one on the left and right sides. After installing the screen, I tried the machine and the fault disappeared. After the installation came back, I waited for half an hour to test the machine. Every half an hour, there was no fault at the start, and I was relieved.
Such a failure can not be repaired anyway, no matter how the board is changed, it is only cured by disassembling the screen and attaching the aluminum foil. Hard bones, after a day, finally solved.
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