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View Full Version : LAPTOP NO POWER, goes back to life when CMOS batt removed


gnawhalak
07-14-2011, 05:28 PM
Help!

Im trying to fix an acer 3620 laptop.

SYMPTOMS:

No power, no lights, nothing.


Diagnosis:

Power adaptor/jack -- ok

Opened to motherboard level.

when i removed the CMOS battery, laptop boots normally.
when i connected back the CMOS battery, first boot is ok. when i remove power jack and plug it back. again, no more power, no lights..



I suspected a bad BIOS... tried resetting the cmos a couple of times already, even doing the power drain (turning off and pressing power for 20s) but to no success...

Any help would be greatly appreciated... thanks!

Jeffreynya
07-14-2011, 05:32 PM
Have you tried another battery?

Knightsman
07-14-2011, 05:49 PM
sounds like bad battery to me...

wtigger
07-14-2011, 11:08 PM
Interesting that a CMOS battery in a laptop would cause those symptoms. I haven't ever seen desktops with dead CMOS batteries cause any issues other than time/date warnings on bootup.

I have a few candidates I can try this on, I have a few dead laptops now ;)

gnawhalak
07-15-2011, 01:33 AM
oops.. sorry.. i forgot to add on my original post..

yes.. i did try replacing the cmos battery in the laptop.. tested with a voltmeter and got a reading of around 3VDC..

so, cmos battery seems ok to me..

thnx jeff, knights, n tigger..


this one is really strange.. first time I encountered this..

Knightsman
07-15-2011, 04:49 AM
Interesting that a CMOS battery in a laptop would cause those symptoms. I haven't ever seen desktops with dead CMOS batteries cause any issues other than time/date warnings on bootup.

I have a few candidates I can try this on, I have a few dead laptops now ;)


Anytime ive tried to make it happen, it doesn't. this is a rare occurrence.

But def something to look out for.

oops.. sorry.. i forgot to add on my original post..

yes.. i did try replacing the cmos battery in the laptop.. tested with a voltmeter and got a reading of around 3VDC..

so, cmos battery seems ok to me..

thnx jeff, knights, n tigger..


this one is really strange.. first time I encountered this..

hmm, in that case, I would say yes a bad bios, I would download the latest one and reflash it. Post here if that fixes the problem.

gnawhalak
07-15-2011, 06:53 AM
so its really quite possible for a bad bios to cause dead laptop/no power...

coz im thinking it could be something else, as a thought that with a bad bios, there will just be no POST, but there should still be power on the board..

hmm.. will look into the possibility of flashing this one.. would just have to let the owner know of the risk first.. if he agrees.. :)

Jeffreynya
07-15-2011, 01:21 PM
How does it run on just laptop battery? Have you tried another power adapter? Agree though, this is quite strange. Let us know how the BIOS upgrade goes.

Knightsman
07-15-2011, 02:39 PM
so its really quite possible for a bad bios to cause dead laptop/no power...

coz im thinking it could be something else, as a thought that with a bad bios, there will just be no POST, but there should still be power on the board..

hmm.. will look into the possibility of flashing this one.. would just have to let the owner know of the risk first.. if he agrees.. :)

Anything is possible with computers these days.

PaulRome
07-15-2011, 05:32 PM
Give this read. Hopefully it helps.

http://vip.asus.com/forum/view.aspx?id=20090420211645831&board_id=1&model=Maximus+Formula&page=1&SLanguage=en-us

Best of luck

gnawhalak
07-16-2011, 10:10 AM
Give this read. Hopefully it helps.

http://vip.asus.com/forum/view.aspx?id=20090420211645831&board_id=1&model=Maximus+Formula&page=1&SLanguage=en-us

Best of luck


good read! thanks.. guess i should not rely on my DMM on a CMOS batt.. better have a new one handy always.. as the one I replaced could have been weak too as a just took it from another computer..


@ paul..

yes.. i did try a different power adaptor..



anyway, just for possible future reference

after removing the CMOS battery and continued putting back the laptop together again, again there was no power in the board.. just blinking light in the battery indicator..

i took it apart again, and it works well if tested with just the motherboard alone..

so, working from there I plugged the power everytime I install a new component one by one and found out that its the DVDROM which is causing the problem.

(yup the laptop was on a bit overused and abused state)

after inquiring with the customer, too bad he won't take the risk of having his bios flashed and was contented with a working laptop with wrong time and no dvdrom..


thanks everyone for the help!