Hello, as the title says, the tabled do not respond to anything. The screen stays black and the charging led never turns on.
So far, i have observed that, when i plug it to the charger, the charger gets hot. Meaning it charges.
I have opened the tablet. The multimeter says the power is runing. 3.7v.
The thermal pad over the CPU is hot.
When i desolder a cable from the battery, the thermal pad cools down and the multimeter says 0v.
When i resolder the battery, the CPU starts to get hot instantly without me pushing the power boutton.
Before all of that, i have tried to charge for 24h then press power button for 30 sec then 3 times in a row.
Also, i have used the tablet for years and it happened suddently. The power boutton was not working very well either for all those years. I had to mash it for him to respond.
Please, help. Thanks.
EDIT : I figured out i can tun the tablet off through the power boutton. If i press it for 30 sec, the thermal pad starts to cool down. If i press again, it gets hot.
Also, if i turn it off and i plug the charger, the pad gets hot again. If i unplug, it gets cold.
It looks like everything is working but the charging led and the screen do not respond.
Hello, thanks for the reply.
I have tested the caps with tablet off so far.
The voltage of the battery is 3V.
Everything supposed to be 0 is 0
Almost everything supposed to be 3.83 is 3 and the 3 lower right caps who are supposed to have voltage are at 0.
I dug around the internet to better understand how it works.
I found out an electronic device will not respond not charge if the battery is too low involtage because the battery will activate its safety mode to avoid complete discharge.
I also found out that you can charge the battery directly with a cut USB cable to give back enough voltage to let it charge with the device.
I’ve done that. I started to charge it at 2.87v on a 5v 1amp external battery who shows me the % left inside it on a screen. The screen stays on when the battery charges something.
At first, the screen did not turn on. But from times to times i unpluged it and tested the voltage on the battery. It was climbing slowly but surely.
After reaching the rated 3.7v of the battery, the charger’s screen turned on and started to show it’s % going down.
So i soldered back the battery to the tablet and pluged it again. The screen of the external battery is lighting up again, meaning it is charging a device.
The thermal pad over the chip shown in the pictures is mildly hot. Before that, the thermal pad was hot near where the battery cables are soldered, not exactly over the chip.
The tablet is still unresponsive tho.
Check these capacitors for short circuit. If there is no short circuit, try flashing the bios.
If this also does not help, look for the axp288c datasheet, perhaps some voltages are incorrect and you need to replace this IC.
