acer 2920 blinking power source

[wideon]

acer 2920 blinking power source just flashing no power getting to main baord

it just flashes the power suppier unit is connected and not getting voltage it gets like 3v then flashes and turns off

laptop dose not start i can see the board has no water damaged

its like a full short is there ant common caps that cause a short

i have fully stripped the laptop and im guessing there bad caps somewhere in the board maybe someone has an any idea how how i can get this board running again

please any info would be great

just found this website looks a really cool site

i know acers are bad for this but where to start ?

also have checked all usb and stuff like for simple shorts


as i said the board here in front of me and awaiting info

Thanks

[selldoor]

Re: acer 2920 blinking power source

Better - anyway have you tested the power supply.
(output voltage with load)
Have you tested the laptop with another supply.

[wideon]

Re: acer 2920 blinking power source

i have tested with a another power surpire and same results

19v strong on the muilt voltage belkin muilt power suppire i use as a tester

[selldoor]

Re: acer 2920 blinking power source

I know very little about laptops- is it totally dead - no lights -no fan.
have you tried with no ram {unless fixed) no hard drive.
Did you try continuity (ohms test) around the power socket to see if it has become detached.
Most people start at the power in socket and trace voltage if any.
A good clear picture of the area around the socket might help.
Hopefully someone having practical experience of acers will be able to help

[wideon]

Re: acer 2920 blinking power source

that's what i am hoping yes i everything with everything removed and the same

i need a acer expert to help

impossible to trace the power as it flicks on and off so to trace the power is impossible really it has to be shorted

[selldoor]

Re: acer 2920 blinking power source

How about the picture? - Is english not your first language?

[wideon]

Re: acer 2920 blinking power source

picture of what

yes English is my first language


but my spelling is very bad

[selldoor]

Re: acer 2920 blinking power source

"A good clear picture of the area around the socket might help." - post4

Ok had to ask, then allowance can be made - read through what you type before you post it. "yes i everything with everything removed" means nothing - remember the people helping may not be able to decipher what you mean and will just give up.
English may not be the first language of a number of our laptop experts.

[wideon]

Re: acer 2920 blinking power source



here is a picture as requested

the 2 red ringed ic are getting very hot when power supply is added

board is empty nothing attached like cpu , memory nothing

there marked u2 and u3 dose anyone have any idea what there used for and can this ic cause a short ..... i.e flashing power supply on and off

think there called mosfet but have no idea as cant see the print on the ic

anyone have a idea what thay are called and will that cause this problem

[selldoor]

Re: acer 2920 blinking power source

They look like mosfets - we will need to know the part number off them to check.

The smaller black rectangular component at D1 is a diode and q1 looks like a small switching transistor ( What is its part number)

The diode you can test - NO Power to the board meter on ohms 2000 test with leads on one way and record the result then swap the leads over and record the result.
If your meter has Diode test you can do the same test using that - tell us which you have done. I am shutting off now but its soon evening in the US.

[wideon]

Re: acer 2920 blinking power source

ok when are you back online as i really need to get this sorted

is on the mofsets

p2003evg

[wideon]

Re: acer 2920 blinking power source

2000k ohms one way 301 other way 299 readings

on diode

[wideon]

Re: acer 2920 blinking power source

i found this too is a schematic for my noard is anyone can help me out

[wideon]

Re: acer 2920 blinking power source

but i see U2 in there but no U3 would i have to repace both of these as thay both are getting very hot

[fddizon]

Re: acer 2920 blinking power source

I want to help but i need to know first what is your skill in using your tester. Do you know how to test a component?

Does your tester has diode tester with sound?

[wideon]

Re: acer 2920 blinking power source

yes it has that please advice

[wideon]

Re: acer 2920 blinking power source

ok as advised i removed U2 and now there power getting in to the board 19v so i just need to replace that any idea where i can get one or can i get one from a old laptop as there no stock based in the uk

[dj_ricoh]

Re: acer 2920 blinking power source

hello
that U2 its a P-Channel transistor 30v from that schematics you putt here.
but the schematics did not show the u3.
you can search the web for similar transistor from another motherboard and replace it but you need to put the same.

[selldoor]

Re: acer 2920 blinking power source

Here is a link to the datasheet

[selldoor]

Re: acer 2920 blinking power source

They are available at ebay but china so 4-5 weeks delay

http://www.ebay.co.uk/itm/5PCs-NIKOS...item4ac05868df

This may be a suitable alternative you need to compare the data sheets also make sure physical size will fit.

http://uk.farnell.com/international-...so8/dp/1857354

https://cdn.badcaps-static.com/pdfs/...9064ed45bf.pdf

Also at RS
http://uk.rs-online.com/web/p/mosfet...633D424F544826

As you didnt bother to say where you are in the England I dont know if there are any trade counters near you

First you should test off the board.
That diode does not look correct - read up on testing diodes.IT may be that only the diode is shorted and not the mosfet.