Short on ASUS Laptop

[m4a2t0t]

Plugged in charger and sparks were coming from jack. Removed board and saw some burn marks on the 8-pin chip ( 4835GM P-CHANNEL ENHANCEMENT MODE POWER MOSFET ) and the center is missing from what looks like a diode.



Plugged in charger with board removed and this chip let out its supply of magic smoke. MB39A132 DC|DC Charger for Li-ion battery https://cdn.badcaps-static.com/pdfs/...5951e1e5c3.pdf



Pin 1 to ground shows continuity - 15ohm.

If I check from the DC Jack inputs (power) to ground I have continuity.

Should I remove that Charging chip and check if there still is a short? How can I find out what that other chip is with center missing? Without buying another mobo? Can I check that MOSFET while it is attached to the board?

ASUS PN# 60-NVKMB1000-C03

Thanks

[dj_ricoh]

Re: Short on ASUS Laptop

Hello!
you need to remove that management chip and see if the short its there if not , replace.
remove that p-chan. mosfet and see if its ok.( ) D to S
p.s. for that diod remove it to and see if its ok. use the MM on the diod mode

[m4a2t0t]

Re: Short on ASUS Laptop

Removed the charging chip and no more short from DC input pins to ground.

Diode show open both directions.

How do I test the mosfet? Diode test both directions 0v. Resistance shows 0 ohm I checked all D>S.

[fddizon]

Re: Short on ASUS Laptop

Removed the charging chip and no more short from DC input pins to ground.

Diode show open both directions.

How do I test the mosfet? Diode test both directions 0v. Resistance shows 0 ohm I checked all D>S.

test it the way like a diode pin123 to pin 5678. one way reading only
if reading is both direction, remove mosfet from board and re test.

[m4a2t0t]

Re: Short on ASUS Laptop

diode test shows 0v both directions. mosfet has been removed from board.

[trebo]

Re: Short on ASUS Laptop

mosfet has been removed from board.

How does it test, now its off the board???

[m4a2t0t]

Re: Short on ASUS Laptop

I only tested it after it was removed

[m4a2t0t]

Re: Short on ASUS Laptop

Is this a suitable replacement for the MOSFET? http://www.newark.com/international-...red%20Products

I don't know what to use for the diode and am having trouble finding anything close to that DC-DC convertor IC.

[fddizon]

Re: Short on ASUS Laptop

replace all 3. diode mosfet and ic

[m4a2t0t]

Re: Short on ASUS Laptop

but what kind of diode? Should I just get another dead mobo?

[spleenharvester]

Re: Short on ASUS Laptop

This is the motherboard schematic mate: http://www.mediafire.com/?csrv45qanno670c

[fddizon]

Re: Short on ASUS Laptop

try getting from old motherboard. getting one from power section too just like where the broken diode was used.

also check mosfets near charging ic.

[m4a2t0t]

Re: Short on ASUS Laptop

all the boards I am finding are no power boards lol.

[fddizon]

Re: Short on ASUS Laptop

see the schematic and get the part number, buy it from ebay or ask someone from here if there is available on hand.

[billpool]

Re: Short on ASUS Laptop

Asus Republic of Gamers Laptop having same issue - smoke coming out when I plug in the power supply - comes out immediately. If anyone has specific info I would greatly appreciate it. I have seen this issue is extremely common by doing google searches but I would like specific circuit board info if possible as it is bound to be a common failure point. Thanks!

[billpool]

Re: Short on ASUS Laptop

finished taking apart laptop to get at MB, photo below shows that one of the pins on the power supply connector is burnt. Help? I assume it's not just re-soldering it?
Thanks, please help me to know next steps. I have it torn apart, not sure what to test besides seeing now where it's fried.
-Bill

[fddizon]

Re: Short on ASUS Laptop

bill, you need to create a new thread for that.
but anyways... you need to remove dc jack from mobo using proper tools
after removing, check the pad pin with black against ground if there is short...
if none, clean the pad thoroughly, apply a little bit of solder to the pads, then return the dc jack if still good.
then solder it nicely.

hope this helps

[billpool]

Re: Short on ASUS Laptop

creating a new thread for this

[hephaistos]

Re: Short on ASUS Laptop

Hi, i`m having the same problem as m4a2t0t and i would like to know if replacing those 3 parts resolved the problem or if it were other parts burnt also.
I replaced the diode and mosfet then i saw that the ic MB39A132 had a "blown like" dot exactly at pin 1.
As i said i would like to know if it resolved the problem those 3 parts because if it didn`t i will throw away the laptop because it doesn`t worth it.
Thank you!

[fddizon]

Re: Short on ASUS Laptop

try replacing the md chip.