ASUS GL553VD power loop problem

[retrorepair2]

I have the above here (i5, gtx1050) that had liquid damage, replaced 3 mosfets, cleared all shorts now tries to power up and power, caps lock and charging lights flash for half a second then hdd light just blips every half second forever.

BQ IC looks fine and definitely no more shorts, power rails are pulsing along with reset, can’t work out what the issue is, does anyone have experience with a similar fault?

someone else posted they had this issue and tried reflashing bios but didn’t solve it.

[retrorepair2]

Here’s what it’s doing. Keyboard LEDs flash too. Would an EC or BIOS reflash help?

also suspect keyboard is shorted since when connected the laptop does nothing at all and the 3.3v on the power button jumper drops to 1.2v

[mon2]

Let me know if you need any of these.

[retrorepair2]

Further to this, because it keeps resetting I can’t reliably see with my DMM if +5VS is being correctly generated. That said, isn’t +5VS a standby voltage? So should be present at all times? Would this indicate the voltage isn’t being generated correctly? It’s not short

[mon2]

Remove all power. Meter in resistance mode. Measure the resistance to ground of each inductor. Hunting for a lower than normal resistance on each power rail.

Test the resistance on the 5v vbus line which are linked to the USB ports. The USB load switch is a common point of failure.

[retrorepair2]

Great I will do, thank you

most read megs

The EC and BIOS would be useful:

Asus ZX553V
GL553VD Rev 2.0
SN H6N0CV01P629223

I guess 4-8 ohm on CPU rail would be normal on inductors

[m1ch43lzm]

Bios requests go here
https://www.badcaps.net/forum/troubl...53vd#post70226

Post there the required info (S/N, board model, laptop model) along with a backup of your existing BIOS, someone there will supply a working BIOS for you to try
Read the BIOS chip 2-3 times, confirm you got a good dump by comparing the 3 files with hex editor, and check that it's not empty (FF FF FF FF ...) before trying another BIOS

[mon2]

Posted the bios images from my database under post # 87

https://www.badcaps.net/forum/troubl...-gl553vd/page5

[retrorepair2]

Thank you really appreciate that. Been going through everything and still not finding any shorts or low resistances except cpu and gpu (2-8 ohm). Think bios is next.

[mon2]

Cpu and gpu are low voltage rails so will be low resistance by design. To me, they look ok.

[retrorepair2]

Ok great, now to figure out how to flash this bios

[m1ch43lzm]

You need a SPI flash programmer, the cheapest is the CH341A, also get a SOP8 200mil adapter, that requires desoldering the BIOS chip from the board, there's also a SOP8 clip but it will take some tries to get it to properly make a connection

Check here for more info https://www.badcaps.net/forum/troubl...21#post1622421

As I said before, it's best to make a backup of the existing contents on the BIOS chip before flashing another BIOS, the original BIOS also contains the serial number and Windows key, that has to be transfered to the "new" BIOS with a hex editor

[retrorepair2]

Replaced a mosfet and accidently bridged 19v and gnd. Nice hole in the board and perminant short so that's that. Damn, this would have been perfect for me. Back to my 2013 Celeron machine I guess.