Skyworth 32E380S boot screen appears after the crash repair - android - Phones Developers

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A few days ago, I repaired a Skyworth 32E380S LCD TV. After the logo appeared, the screen turned dark, the backlight failed, and the remote control didn't respond. The issue persisted even after testing the unit again.





After an initial analysis, I suspected a software problem. Both [Sichuan Integrity LCD Repair] and [Wuhai Yuxiang Super Edition] provided U-disk upgrade programs and instructions.



The U-disk upgrade program can be downloaded from this link: http://pan.baidu.com/s/1gfQpXL5, with password: 8axk.

I used the third method—saving the upgrade file to the root of the USB drive and renaming it to "install_keypad.img". It's important to copy the name exactly, not type it manually, to avoid errors. The local upgrade method differs slightly from the image shown. After booting, there was no red light at all. Once inside the upgrade menu, the indicator light didn’t flash alternately.

The correct procedure is: Immediately after powering on, press and hold the "Menu" button until the red light starts flashing, then release. After a few seconds, the upgrade screen will appear. The process takes about one minute. Do not remove the USB or turn off the TV during this time. Wait until the upgrade completes, then safely remove the USB and reboot.





After a successful upgrade, the TV displayed normally. The AV input worked well with the DVD signal, but the TV channel search only found one station. Since the user uses digital TV, I left it for later. However, when I turned it on again at night, the issue remained. Re-uploading the firmware twice did not help.

After further analysis by the group, it was determined that there might be a hardware issue. Sichuan Chengxin Master provided the motherboard schematic. After careful measurements, we found that the voltage output from U19 on the motherboard was abnormal—initially 1V, then rising to 2V. Even when the voltage stabilized at 2V, the TV still couldn’t find any channels.

Comparing the schematic, U19 should output 5V, which powers the high-frequency head. We tried replacing it with a similar LD1117 from an old board, but it gave 7.5V and caused the system to crash. Since we couldn’t find a suitable LD1117, we decided to try a 7805 regulator instead. After installation, the TV booted up normally, and the automatic channel search function worked properly. The fault was completely resolved.









Here’s the motherboard schematic for Skyworth 5800-A8R580-0P30: Skyworth 5800-A8R580-0P30.pdf

A big thank you to Sichuan Integrity Master, Wuhai Yuxiang, Wangji, Xiaoqiao, Liushui, People, Ttfx, and other technicians who provided support and helped analyze the issue. As the saying goes, “Many hands make light work.” This experience was truly rewarding.