Dell XSP 15-9570 laptop has a dark screen when it is turned on. Visually, the BIOS and CPU have been passive. It is wrong to measure the voltage of EDPVDD to 0V, and then measure that the 19, 20 and 21 pins of the screen are also 0 V. Dismantle it and replace it with a good one, then connect it with electricity for testing. When it is turned on, the EN voltage is 1.2, and it is turned on normally.
Lenovo ThinkPad E540C notebook is powered on and powered off. After removing the capacitor, the measured resistance value is more than 300 ohms (the one after disconnection). After the capacitor is installed, the computer will be normal
Asus X540UP notebook can't be turned on, the BIOS hasn't been moved, the CPU voltage is normal, turn on the bitmap, look for the small 6-pin conversion tube PU8804, disassemble it directly, and then connect it directly from the resistance of R0633 at the back of the CPU, then power it on, and the current is 0.26-0.54-0.68-0.48-0.53-0.44-0.75.
Lenovo Xinchao 7000-13 notebook has standby current without triggering multi-fault maintenance. [Machine model] Lenovo Xiaoxinchao 7000-13 [Fault phenomenon] The notebook will not be triggered when there is standby current. [maintenance process] Repair a small trendy 7000-13 notebook computer with a…
When the current was debugged to 2V and burned, it immediately became more than 4A. I touched a chip PU18 SA with my hand to supply power, and removed the re-burned machine, but there was no current. First change the SA chip, then continue to change the CPU and graphics card, and restart the current of 1.85-1.96-2.15-2.43. There is no power failure, so it is installed and tested, and the machine lights up perfectly.
Lenovo Xiaoxin Air13IWL notebook standby short circuit, when the current is adjusted to 2V, the current becomes more than 4A. Under a sticker, there is a capacitor next to the standby chip PU701, which can be directly removed.
Second, the touch panel keyboard of Apple MacBook A1707 notebook can't be used. It was directly installed on the machine for measurement. When the problem was found, the interface voltage was wrong, so the interface was directly changed, tested again, and troubleshooting was carried out.
The TPN-Q214 notebook can't be turned on when it is flooded with water, and the current is directly 0.15. There is a short circuit in this case, so it is suspected that there is a problem with the chip, so just disassemble it and try another one. Let's see if it's the same on the 8th generation machine. It's a 5V=7F [model RT3612C]. It seems that it can be exchanged with each other, replaced, troubleshooting, and maintenance is over here.
Dell 15-5547 notebook does not respond when pressing the switch, and the small inductance next to the small battery is 0 to the ground; One of the nearby capacitors is a little black and has a small crack. After turning off the capacitor, I found another capacitor to repair it