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

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KONKA LC32GS80C - A No-Maintenance TV Model: KONKA LC32GS80C

Fault: The TV turns off automatically.

Repair Process: Look, Smell, Ask, and Cut!
First, I started by looking at the whole unit. It was clean, no water stains or dirt on the power cable. Then I smelled it—no obvious burnt smell, which made me a bit curious. Next, I asked the user about the issue.

The user is a couple who rarely uses the answering machine. They only occasionally check for news. After some friendly questioning, the female user finally admitted that the TV broke down and couldn’t be fixed elsewhere, so they came to me for help. (Good people! Lucky I didn’t have a knife; otherwise, I might have had a real problem.)

The user explained that the TV would shut down randomly but could be turned on again. Later, even the LED lights became dim. Based on this, I suspected a power supply issue and quoted a repair cost. They agreed immediately. I really like users like them.

After opening the case, I found the power board was quite clean, suggesting the previous technician did a good job. There were no signs of burning or swollen capacitors. I checked with a multimeter and found that the standby voltages (5V, 12V, 24V) weren't stable. The fuse was blown, and the FET (18N50) was damaged. I replaced it with a 20N60 since I didn’t have the original part.

After replacing, the standby voltage still wasn’t correct. I used a 12V bulb as a dummy load to simulate booting. The output stabilized, and there was no fluctuation. I connected the motherboard, and everything looked normal—power supply, amplifier, and power were all working fine. The TV booted up normally with the "KONKA" logo.

But then the user mentioned another issue: the TV would automatically shut down after about 10 minutes of use, though the indicator light remained on. I thought maybe it was a software or data issue, but the test showed no power failure. Suddenly, I suspected the button board. I replaced it with a new one, and the problem didn’t reappear for over half an hour. The sound and picture were both normal, and the TV was delivered back to the user.











Small Note: Never underestimate small details. Sometimes, the smallest component can cause big problems. Thanks for watching! 😊