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

Photocoupler

KONKA LC32GS80C - A no-maintenance model. The user mentioned that the TV occasionally turns off by itself, but it can be turned on again. After some troubleshooting, I found out that the problem wasn’t with the power supply or the main board. It was actually a faulty optocoupler that caused the issue. The repair process started with a visual inspection—no signs of burning or damage were found. Then I checked the voltage levels: 5V, 12V, and 24V were all stable. However, after replacing the optocoupler (UW903) and the associated 431 chip, the TV still had issues. The standby voltage wasn’t stable, so I used a 12V bulb as a dummy load to simulate boot-up. That helped, but the machine would still shut down after about 10 minutes. At this point, I suspected the button board. Replacing it fixed the issue. The TV worked perfectly after that, and the user was happy with the result. I always make sure to check every possible component, even if it seems unlikely. Sometimes, the smallest parts can cause big problems. This case reminded me that attention to detail is crucial in repairs. Even though the machine looked clean and well-maintained, the root cause was hidden in a small component. It's also important to communicate clearly with the user, as their feedback can guide the diagnosis. Don't skip any steps, even if they seem minor. Every detail matters. Thanks for reading!

Small note: Never underestimate the importance of every detail. 【Thanks for watching】