Huawei Magicbook m/b DAH98AMBAD0, dead

[DrFalken]

Just arrived a Magicbook with m/b DAH98AMBAD0 completely dead, power LED stay OFF.
Checking with thermal camera I see a chip labeled 4GA "pulsating".
4GA code point me to "FT521GAb"="LDO, Dual out, Vout1/Vout2=2.8V/1.2V±2%, 250mA, +CE"
Maybe something is shorting it ?
What can I check ?
Can't find it on the attached schematics - https://www.badcaps.net/forum/troubl...c-or-boardview

[kalilinux25]

Re: Huawei Magicbook m/b DAH98AMBAD0, dead

Just arrived a Magicbook with m/b DAH98AMBAD0 completely dead, power LED stay OFF.
Checking with thermal camera I see a chip labeled 4GA "pulsating".
4GA code point me to "FT521GAb"="LDO, Dual out, Vout1/Vout2=2.8V/1.2V±2%, 250mA, +CE"
Maybe something is shorting it ?
What can I check ?
Can't find it on the attached schematics.

what is the voltages of the pins, after check the resistance of eveery pin

[DrFalken]

Re: Huawei Magicbook m/b DAH98AMBAD0, dead

what is the voltages of the pins, after check the resistance of eveery pin

Voltages of nearby components fluctuate when fed from the original power supply.
I've also tried another power supply...same behavior.
This morning I've injected up to 4.5V (starting at 1V@1A) on the main power rail (this laptop is powered by a USB Type-C) and starting from 4V this chip immediately overheats on the thermal imager.
So I've removed this "4GA" part and I'm looking for the datasheet to find a replacement
Note: The voltages do not fluctuate with the bench power supply.

[kalilinux25]

Re: Huawei Magicbook m/b DAH98AMBAD0, dead

Voltages of nearby components fluctuate when fed from the original power supply.
I've also tried another power supply...same behavior.
This morning I've injected up to 4.5V (starting at 1V@1A) on the main power rail (this laptop is powered by a USB Type-C) and starting from 4V this chip immediately overheats on the thermal imager.
So I've removed this "4GA" part and I'm looking for the datasheet to find a replacement
Note: The voltages do not fluctuate with the bench power supply.

better try to change it already

[DrFalken]

Re: Huawei Magicbook m/b DAH98AMBAD0, dead

Found !
4G(A) = RT1711H Programmable USB Type-C PD Controller

[mon2]

Re: Huawei Magicbook m/b DAH98AMBAD0, dead

Excellent find.

[matheus30]

Re: Huawei Magicbook m/b DAH98AMBAD0, dead

Found !
4G(A) = RT1711H Programmable USB Type-C PD Controller

I have the same problem, Did it work for you when you changed it?

https://www.badcaps.net/forum/troubl...BA-celsius-hot

My board is HUAWEI Matebook D15 Laptop - Mod: BOB-WAH9 - Motherboard: DAH98MMB8D0 REV D , but I think that is the same IC

The last letter 4GA -> 4G"D" is date packaging

[DrFalken]

I have the same problem, Did it work for you when you changed it?

https://www.badcaps.net/forum/troubl...BA-celsius-hot

My board is HUAWEI Matebook D15 Laptop - Mod: BOB-WAH9 - Motherboard: DAH98MMB8D0 REV D , but I think that is the same IC

The last letter 4GA -> 4G"D" is date packaging

Sorry can't help 😥
If I remember correctly, the customer took the laptop back without repairing it