a little troublesome maintenance experience - appliance repair

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I had a Sharp LCD-32L120A with a black screen and no sound. At first, I thought it was a backlight issue. But after opening the cover and testing, I found that the backlight was actually working. Then I checked the voltage on the edge board and found 12V for the screen power supply. Initially, I suspected a problem with the screen or the board. I informed the customer about the potential issue and suggested bringing it back for repair, noting that the repair chance was around 50%. The customer agreed. When I got home, I opened the panel and measured the VGH and VGL voltages on the screen board, but they were both zero. Even when I applied 12V, there was still no voltage. That was strange—12V was shorted to ground. After removing the TV power supply chip MAX17126, the short disappeared. I then checked the 3.3V power supply and found it was also shorted. Removing the MT71168 chip fixed the 3.3V short. I got a screen board from Wenzhou, replaced two chips, and installed a 12V fuse. However, the screen turned white after booting up. Later, I discovered that the problem was in the edge of the screen and the edge board. Based on my experience, I didn't panic. I just blew out the screen cable and re-soldered it. After powering up, the test machine worked, and the repair was finally complete. Another tip: I found that the MAX17126 is similar to the CM501. I compared them and confirmed that they can be used interchangeably. If you can't find a good CM501, I recommend using the MAX17126 instead. Here are some real photos of the process: