share asus 1215b flashing power led (solved)

[holmes222]

hi .. sharing an experience with other here
my daughter laptop broken..
she said that her friend use the laptop and moving data through usb flashdisk
after a couple minutes, the laptop went shut down it self
press the power button result in blink/flashing power led, laptop won't turn on
reset bios thru shorting pin below memory slot, change memory not help at all
being not warranty anymore (only 1year warranty), open up the laptop.
powering outside the case, still flashing power led no power
first diagnose, suspecting the usb port or chip failed
disassemble all connector, and found the culprit
its a wifi card that makes problem , powering without wifi card, the power led turn on normal and the laptop turn on normaly.
insert wifi card, mek power led only flash and laptop not turning on
replace wifi card with another card, make the laptop turn on and off normaly without problem.

curious why the wifi card get problem/indicating shorted and make the whole system wont turn on at all ??

[spleenharvester]

Re: share asus 1215b flashing power led (solved)

The WiFi card shares either +3.3VAUX or +5.0AUX rails (I think both are present if I remember correctly?). If a component on the WiFi board goes short, it will short the aux rail(s) similar to how a bad ceramic cap on the board itself might, resulting in the laptop being unable to power on.

Eitherway, nice find. I've never actually seen this happen before.