Asus x55a problem

[heavymachines]

Re: Asus x55a problem

please list actual readings like this .001 or 1.111 whatever you're getting. if high resistance or almost dead short...

[Morsus]

Re: Asus x55a problem

Nijesi me dobro ukapirao...na programator da ga flesujes...ne diraj ostalo jer je mozda u redu...Nizak otpor moras da imas u kolu aktivnih cipova...to je normalno...

To be fair to the rest of the forum I suppose we should continue on English
I'm not sure how to flash bios without a display.

Readings do vary about +-0.10V every time I measure on the bottom transistor. All other values are fixed.

[heavymachines]

Re: Asus x55a problem

You would need need one of these..eBay item number:182492676824
to be able to flash it not being able to boot laptop. Or buy a preprogrammed bios and soldier it in or make your own interface to ic and rom software to flash it...


Readings are fixed, in diode or ohms? Actual readings please .001 on source of fet? 111? , without designators and pin numbers with actual readings makes things very confusing and can give wrong data.

[Morsus]

Re: Asus x55a problem

Okay, this is where I am now. Since I don't own a device for bios programming or programmable bios chip I discarded that idea. (Couldn't find the item by that number either, but I did google a lot).

I took all 3 transistors off for testing and the each show 750 on diode mode between drain and source. Sooo the transistors should be good, right?

I didn't try to take caps off since they have a plastic bottom and I didn't want to make a bigger mess than it already is. (you can see that the pink/red color did come off from caps top)

So, can I test anything else now while I have these off?

[Morsus]

Re: Asus x55a problem

bump

[Morsus]

Re: Asus x55a problem

Update:
Without processor and these 3 transistors the pins on bottom connector are shortened. First two are shortened and second two between themselves.

Also I made another image of all contacts shortened to the ground.

[heavymachines]

Re: Asus x55a problem

If you're certain it is shorted within itself replace. that cap with missing paint should be replaced got way too hot. Not enough flux used or none at all and add fresh soldier and flux to get it too come off with iron at less time therefor with less heating time. Chipquick works good for removal of smd devices. Use regular flux for putting back in. You check for shorts on mosfet between gate and drain. https://www.youtube.com/watch?v=fOGAhaVH06I
Again http://mayohardware.blogspot.com/201...g-mosfets.html.

[piernov]

Re: Asus x55a problem

No I think it's perfectly fine, nothing shorted here.
(the only thing would be the 3 MLCC caps between the two coils and the CPU socket on the left, but it's probably fine)
You get good VCore so this section is perfectly fine in my opinion.

Does the OS boot anyway? (ie. you can hear the hard drive heads moving)

[Morsus]

Re: Asus x55a problem

I will check the cap that has no paint on. Also will replace the 3 MLCC caps.
Hmm.. not sure anymore. I remember hearing it work but I can't remember if HDD started or not :/ I will assemble it all back together tomorrow to start it again and make sure if its starting or not.

[Morsus]

Re: Asus x55a problem

Okay I have assembled all back together started it and the HDD did start. So everythign is basically working but the screen internal or external. I also took the first cap in row below CPU witch showed up to be a little bad (about 450uF instead of 560uF) but I don't think that it is the culprit. I am looking for a replacement cap atm.

[piernov]

Re: Asus x55a problem

Ok so the OS is booting (hard drive heads moving for quite some time)? Caps lock/Num lock works?
Check voltage between PL8004 and ground near the CPU socket.
It's the inductor on the right of the CPU socket in this picture (the big gray square):
https://www.badcaps.net/forum/attach...0&d=1490374156

Also do you have backlight or is the screen doing anything?

[piernov]

Re: Asus x55a problem

I also took the first cap in row below CPU witch showed up to be a little bad (about 450uF instead of 560uF) but I don't think that it is the culprit. I am looking for a replacement cap atm.

It may be the issue, but I'm not sure which cap you're talking about?

[emmanuelbill1988]

Re: Asus x55a problem

please just cook the board,it will work

[cacla]

Re: Asus x55a problem

Pls tray to reprogram bios with this bin its working bin file

[Morsus]

Re: Asus x55a problem

No backlight no anything 100% dead, same on external screen.
I cant measure anything until I replace the missing cap.
I am not cooking the board.
Also I can't reprogram the bios since I don't have the right equipment (I am in process of getting it tho).
Okay, back to the cap. I have nowhere to buy same one at my place all I got are these:
Original cap - 560uF / 2.5V (2J2)
Spare ones I got?
651uF/6.3V (FP5K/FP) or 820uF/2.5V (E110/ULR).
Could I use any of these?

[cacla]

Re: Asus x55a problem

I know this board you have problem with bios if you wish this board to work you must flash bios on programmer.

[cacla]

Re: Asus x55a problem

Here repair guide

[piernov]

Re: Asus x55a problem

You can flash the BIOS using a Raspberry Pi for example. Always remember to make a backup. It would be preferable that you try this before trying to change components since you may damage the board by doing so.