asus ux305ca was dead, now works, but battery is not charging

[rediii]

hello guys,
i fixed an asus ux305ca which was not turning on at all. gate-vcc was missing on the first fet (check picture), i removed it and bridged source and drain with a wire (finding the gate-regulator is a rabbit hole...). the battery of the device was completely dead and i think it fried the mainboard. i just bought a new battery (aftermarket, but ok) and this would not charge at all. if the battery is not plugged in, i can measure around 0.845 v on the coil (check picture with mark). i think the battery ic is bad or/and there is more missing than the first gate-vcc of the first fet after the charging port. if the battery is plugged, the laptop ist starting, but the charger voltage would not pass through the dcdc-step down for the right battery charging voltage. laptop is otherwise totally fine. thanks in advance! any ideas?

[mcplslg123]

Re: asus ux305ca was dead, now works, but battery is not charging

That wont work. The gate of the first mosfet will be equal to souce voltage in this arrangement whereas it should be higher or lower then source depending on whether its n channel or p channel mosfet. Without the correct gate voltage at dc in mosfet, charging circuit will never work whatever you do.

[rediii]

Re: asus ux305ca was dead, now works, but battery is not charging

That wont work. The gate of the first mosfet will be equal to souce voltage in this arrangement whereas it should be higher or lower then source depending on whether its n channel or p channel mosfet. Without the correct gate voltage at dc in mosfet, charging circuit will never work whatever you do.

so there are missing multiple gate-vccs on the board? or do you think the charger AND charging gate are coupled? i don't have any schematics, it's a waste of time to search for the gate-elements...

[SMDFlea]

Re: asus ux305ca was dead, now works, but battery is not charging

Boardview: https://www.badcaps.net/forum/showpost.php?p=818861

[rediii]

Re: asus ux305ca was dead, now works, but battery is not charging

Boardview: https://www.badcaps.net/forum/showpost.php?p=818861

thanks man, but which program do i have to use (openboardview cant open the file)

[SMDFlea]

Re: asus ux305ca was dead, now works, but battery is not charging

openboardview can open it with the .fz key.

[rediii]

Re: asus ux305ca was dead, now works, but battery is not charging

openboardview can open it with the .fz key.

do you know another free software then? would help me a lot, thanks

[SMDFlea]

Re: asus ux305ca was dead, now works, but battery is not charging

Read your PM .

[mcplslg123]

Re: asus ux305ca was dead, now works, but battery is not charging

so there are missing multiple gate-vccs on the board? or do you think the charger AND charging gate are coupled? i don't have any schematics, it's a waste of time to search for the gate-elements...

You need to have some patience in trouble shooting a laptop mobo. That's all i want to say.

[rediii]

Re: asus ux305ca was dead, now works, but battery is not charging

You need to have some patience in trouble shooting a laptop mobo. That's all i want to say.

already solved the problem, thank you guys! sry, but i have a lot of work to do, so no time

[brew99]

Re: asus ux305ca was dead, now works, but battery is not charging

So what was the solution then?

[rediii]

Re: asus ux305ca was dead, now works, but battery is not charging

So what was the solution then?

battery ic was faulty and i replaced n-channel mosfet near charging port!

thank you guys!