Hisense LCD TV TLM42V78K crash failure repair example - appliance repair - Huaqiang electronic network

MOS Power IC Full Range

Key Source Letter Crystal Passive 1612 24MHZ 26MHZ Authentic Spot

The Hisense TLM42V78K LCD TV experienced a crash. After checking the power supply board, the output voltage was found to be normal, so the issue was traced to the motherboard. Further inspection revealed that the DRAM power supply voltage was only 0.92V (the normal value is 1.09V). The ground resistance of the DRAM was within normal range, indicating that the DRAM itself was not damaged. Next, the DC-DC power circuit was examined. The 5V supply from U3 was confirmed to be normal, but the output from U3 was faulty at 0.92V. The diode D62 was checked and found to be in good condition. Replacing U3 did not resolve the issue, and further testing showed that C512 was also functioning properly.