KONKA Konka LC32GS80C three no maintenance repair small note - appliance repair - Huaqiang electronic network

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KONKA Konka LC32GS80C three no maintenance small note model: KONKA Konka LC32GS80C

Fault: three no

Overhaul: look, smell, ask, cut!
Look at the beginning: the whole machine is quite clean, no water stains, etc., the power cord is not deformed or dirty, then the next is the smell;
The first place in the news: the whole machine has no obvious smell; (a little doubt Ask questions;

Asked to be centered: According to the user (two husbands and wives), the answering machine is rarely used, but only occasionally came back to see what the news is. He continued to ask questions with the spirit of asking the bottom, and the female user finally broke the machine and could not be repaired elsewhere. I just came to look for help; (good guy, fortunately, I didn’t have a knife; otherwise I really got it.) I asked about the initial failure of the machine. The user’s response is that the machine is automatically shut down from time to time, but it’s good to turn it on again. Later, even the finger lights are not bright, so I have a general answer in my heart, so the user is quoted red and black, the user readily agreed! I like this drop user!

After cutting the temple: Take off the power board and repair it separately.
Scalpel ), the machine is quite clean; it is estimated that the former maintenance master's manual, this habit is worthy of praise; the eyes have not found traces of burnt, capacitance 'pregnancy', stethoscope (multimeter) ); standby 5V, 5V, 12V, 24V are not 3.15A
Insurance reimbursement, power supply part of the FET is damaged (the former master changed 18N50 block), with a 0.1Ω starting resistance increase (damage), there is no reason, if it is so simple, it is estimated that it will not go up This is coming, continue to check; found that there is no abnormality in the periphery of the power management chip, and the last few tubes are no longer the case? Is it optocoupler? ! (There was a repair case) Then went straight to the optocoupler; the power board of the machine has three optocouplers. When the UW903 was inspected, the optocoupler was found to be damaged, and the 431 attached was also hung. Finally, replace the damaged parts (because there is no 18N50 on hand,
Therefore, with 20N60 replacement), the standby voltage is measured, but there is no 5V, 12V, 24V; use 12V bulb to do the dummy load simulation boot (start with the resistor is not good The latter three are all out, and there is no abnormal fluctuation in the smooth; connect the motherboard, the indicator light is measured, the U power supply is normal, the power amplifier is also normal, the power is also OK, press the power button, the 'KONKA Konka' boot log comes out; but the problem comes The user is starting to talk about the automatic shutdown barrier from time to time. The machine will automatically shut down after about 10 minutes of power-on, but the indicator light is on; don't worry, turn it off and then turn it on again, but it will be fine, but after a few minutes!
Is it a data problem? ! There is no power failure under the test standby, the latter three are not; suddenly found that the button board is suspect, decisively replace the new button, the old time failure does not occur for half an hour; turn on the sound signal of the machine Both are normal and the machine is delivered half an hour later; the machine is repaired.










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