Found that standby is 0. According to the drawing, measure each pin of the chip, burn the machine directly, and feel that the PC388 capacitor is seriously hot, and it will not be short-circuited after being pulled out.
3V standby, replaced by an AMS1117-3.3, suspected that there is something wrong with the graphics card chip, turned off the power, removed the power supply inductor of the graphics card, and powered on again. The machine runs normally, the fault is repaired, and the maintenance is over.
There was no response when pressing the power button. I found that the vicinity of the USB conversion chip was hot, and the chip was removed, or it was against the ground, and the capacitor next to it was removed. Power-on test, perfect lighting!
Lenovo notebook Y7000 2019 boot screen, found that the graphics card model is 2060, drive exclamation point, error 43. After removing the main memory, everything will be easier. Deal with the pad first, and then solder the new memory.
Before dismantling, there was no corrosion by visual inspection, and it was found that a fuse F7140 was 8.45V at one end and 4.1V at the other end, which jumped repeatedly.Drag a wire directly, and then power on it to trigger automatically. After repeated tests, it is normal.
Visually, there is no corrosion where there is water. When the current is turned on, it is found that there is no current for a while, and it is concluded that there is a short circuit. When I opened the drawing, I found that the 8690 pipe PU21 and the PU23 pipe were passages. I directly removed the hot short-circuit pipe PU21 and re-burned the machine, and it was normal.
The second repair of ASUS Flying Fortres…
It is found that the 6-pin EN also has 0.5V electricity, which is abnormal. After disconnection, LDO3 outputs normally, and the EN emitted by EC also has 3V, indicating that this is the problem.
The notebook is not turned on, and you see a broken line after running, but you have to remove the capacitor to make it up. Direct flying line, power-on test, perfect lighting machine.