ASUS ZenBook UX363J component identification

[sect-sin]

I have an ASUS ZenBook UX363J (motherboard UX363JA Rev 2.2) with water damage, no boardview, no schematics.

One of the resistors disintegrated (see attachments), and I have no idea what value it is. It is connected to a 4x4 QFN charging chip (?) by Monolithic Power with the marking M2940A. I could not find any datasheet for it, so I cannot use that to find out about the value of the destroyed resistor.

If anyone has such a board, please measure the resistor and let me know.

Thank you in advance!

Cheers,

sect-sin

[Sephir0th]

Re: ASUS ZenBook UX363J component identification

Almost the second picture on Google search gives the clue. The rail is related to VIN_SEN and is basically a voltage divider consisting of 133K Resistor connected to GND and 2M Resistor connected to Main Power rail.

[sect-sin]

Re: ASUS ZenBook UX363J component identification

Almost the second picture on Google search gives the clue. The rail is related to VIN_SEN and is basically a voltage divider consisting of 133K Resistor connected to GND and 2M Resistor connected to Main Power rail.

Sephir0th,

Thank you immensely for your help. So it must be a 2M resistor then, I will confirm tonight whether the other resistor is 133k.

Just for my learning, what was the exact searchphrase you used to find this tidbit of schematic on google?

Cheers,

sect-sin

[Sephir0th]

Re: ASUS ZenBook UX363J component identification

Still need to be a bit careful or in other words maybe some testing necessary since we don't exactly know the source voltage of the schematics and whether it fits to your main power rail voltage.
However if the remaining resistor fits to one of the possibilities you should be fine

[sect-sin]

Re: ASUS ZenBook UX363J component identification

Still need to be a bit careful or in other words maybe some testing necessary since we don't exactly know the source voltage of the schematics and whether it fits to your main power rail voltage.
However if the remaining resistor fits to one of the possibilities you should be fine

I just managed to confirm that the other resistor is 127k, so I guess you are right, the disintegrated resistor must be 2m.

Thank you for your help and insight. There is still much to restore on this board, and I am pretty sure the previous owner poured some incredibly nasty alien fluid into this notebook. It is easier to solve the problem of light speed travel then to get it clean.

Once I am finished and testing, I will let you know the outcome.

Cheers,

sect-sin

[sect-sin]

Re: ASUS ZenBook UX363J component identification

Hi,

I just wanted to give you an update. After all the restoration work I have put in, it turns out that the southbridge integrated in the CPU is shorted.

Since I do not have knowledge and equipment to do a CPU swap, I will have to bury this board. RIP.

Thank you anyway for your help.

Cheers,

sect-sin

[Sephir0th]

Re: ASUS ZenBook UX363J component identification

This was probably a very disappointing experience in the end but thank you for feedback about the outcome.

I guess you figured out a shorted 1.05V supply?

[sect-sin]

Re: ASUS ZenBook UX363J component identification

This was probably a very disappointing experience in the end but thank you for feedback about the outcome.

I guess you figured out a shorted 1.05V supply?

Sephir0th,

Yes, it was very shitty. Due to severe corrosion, I had to replace all DrMOS supplying VCore and the Southbridge, the charging chip, as well as around 10 capacitors in the VCORE area. Not to mention rebuilding a lot of missing pads. The 1,05V supply is not shorted now, and I do not know whether it was shorted because of the disintegrated parts.

As the water damage hit the VCORE area right above the CPU, it is also possible that water got under the CPU, and corrosion caused a short there.

I am thinking about giving it a last shot with reheating/reflowing the CPU. I ordered a preheater, should arrive soon.

Cheers,

sect-sin

[piszpunta]

motherboard UX363JA Rev 2.2
Please component identification

[ro.man]

motherboard UX363JA Rev 2.2
Please component identification

5 it is some thermal sensor like UP1905AMA8 used on older models. I'm currently working with similar board and looking for same component... Going to try UP1905AMA8 instead as circuit looks very same.