Toshiba satellite A200 (non Nec/Tokin OE907) locks up when plugged in.

[fabiog]

I have a satellite A200-221 that locks up when plugged in to the mains but works fine with battery.
Another thread on this site suggests replacing a big cap Nec/tokin OE907 is responsible and many people have repaired this problem by replacing the chip itself with the same one or 4x tantalum smd caps.

But this is not my case since I do not have that chip instead many small capacitors in it's place ,I have tried another power adapter ,it seems to be doing it in safe mode also.
Any help will be welcomed.

[b700029]

Re: Toshiba satellite A200 (non Nec/Tokin OE907) locks up when plugged in.

Then try replacing those small caps instead, because they are performing the same vcore filtering function (on the low side). Check the high-side caps too, the ones before the inductors and MOSFETs.

[fabiog]

Re: Toshiba satellite A200 (non Nec/Tokin OE907) locks up when plugged in.

Thanks for your response b700029.
Should I also replace the Tantalum caps c53-c58 that are on page 6 of schematic.

[openupshop]

Re: Toshiba satellite A200 (non Nec/Tokin OE907) locks up when plugged in.

Then try replacing those small caps instead, because they are performing the same vcore filtering function (on the low side). Check the high-side caps too, the ones before the inductors and MOSFETs.

Hello b700029 and fabiog, (fabiog, I hope you don't mind me jumping in on this thread as well)

I have the same issue as fabiog, Toshiba L675D-S7049 works great on battery, but freezes immediately after plugging in or soon thereafter. However, I too do NOT have the Nec/Tokin OE907.

I have tried countless other solutions as well, to no avail.

Can you please tell me which capacitors to change, I am attaching images of both sides of the motherboard which if you zoom a bit, you can see the capacitors, some of which are:

3 0E5 220 6.3V
3 0G4 390 2.5V
3 0J4 VLPS 330 2.5V

Here I need your expertise...
Can you please guide me on which to change and with what?

If you need me to attach other images, or to post any additional information, please let me know...

[b700029]

Re: Toshiba satellite A200 (non Nec/Tokin OE907) locks up when plugged in.

Thanks for your response b700029.
Should I also replace the Tantalum caps c53-c58 that are on page 6 of schematic.

C53-58 are the low-side caps, if you can remove the CPU from the socket like it says and measure the capacitance and ESR between the +VCC_CORE and ground. As it says the ESR of all of them in parallel should be <1.5mOhm and the total capacitance > 1980uF.

The high-side caps are the ones on the top right of page 43.

[fabiog]

Re: Toshiba satellite A200 (non Nec/Tokin OE907) locks up when plugged in.

At the moment don´t have an ESR meter to check only a normal multimeter ,I have another dead board that worked fine with current ,I might try changing the caps with those "good" ones and see what happens one cap at a time.
will try the lower caps first.

I don´t have a camera at the moment but here is an image of the board.
http://www.tomshardware.co.uk/forum/...070_20_50.html
If you scroll down to the center of the page you can see on the top image the C56,57,54,55 and c17 on the right ,the small ceramic caps in the center i think are also to blame.

[xaviero1412]

Re: Toshiba satellite A200 (non Nec/Tokin OE907) locks up when plugged in.

check vccore without processor first... if its +1.05V then its ok (+ mean higher then)
or try add more Caps at empty-slot-caps

[fabiog]

Re: Toshiba satellite A200 (non Nec/Tokin OE907) locks up when plugged in.

Well there are two empty spaces labeled C58 and C53 but with no caps as shown on page 6 of schematic I wonder if I add 330uf caps there then it will work.

[fabiog]

Re: Toshiba satellite A200 (non Nec/Tokin OE907) locks up when plugged in.

I changed the lower caps with ones from another board and problem persists even added 2 caps to C58 and C53 and also same problem,
either the caps used are also bad or I need to also replace the high end caps as suggested by B700029 on page 43.
I also believe one of the small ceramic caps in the center that start from C37-C52 , PH1 is right in the center.

[xaviero1412]

Re: Toshiba satellite A200 (non Nec/Tokin OE907) locks up when plugged in.

u have to check vccore without processor, if it below 1 volt do this:
according to your schema toshiba a200 la 3481,
C53 C54 C55 C56 C57 C58 are caps for vccore 6x330uf

if u have no esr-meter, simplest way is change all of it with new ones.

if u check the vccore without processor is higher then +1.05 , stop there.

[fabiog]

Re: Toshiba satellite A200 (non Nec/Tokin OE907) locks up when plugged in.

How would I check the vccore ,which pins to check?

[xaviero1412]

Re: Toshiba satellite A200 (non Nec/Tokin OE907) locks up when plugged in.

turn your volt-meter to 2 or 20 voltage reading, put black (minus/ground) to ground and red (positif) to any of the positif polar of 6 caps mentioned above.
in your case, it will about (maybe) 0.9v or lower

[fabiog]

Re: Toshiba satellite A200 (non Nec/Tokin OE907) locks up when plugged in.

I'm actually getting 0v without CPU installed ,I connect mains power ( am I supposed to turn on the laptop?) I get 19v at DC jack but when I place red probe on any of those caps and black on any ground source I get 0v.

[xaviero1412]

Re: Toshiba satellite A200 (non Nec/Tokin OE907) locks up when plugged in.

100% vccore problem, replace them

[fabiog]

Re: Toshiba satellite A200 (non Nec/Tokin OE907) locks up when plugged in.

Tested vccore with laptop switched on (before I and got 1.5v ,so only way now is to replace caps with new caps and test again.

[xaviero1412]

Re: Toshiba satellite A200 (non Nec/Tokin OE907) locks up when plugged in.

waiting for your success story....

[damdam]

Re: Toshiba satellite A200 (non Nec/Tokin OE907) locks up when plugged in.

Did you replace the caps? Results?
I have a Toshiba A200-23m that shuts down when plugged in. Also it doesn't charge properly, I think. Any advise?
tnx in advance.

[fabiog]

Re: Toshiba satellite A200 (non Nec/Tokin OE907) locks up when plugged in.

I don't have that laptop anymore ,and never got to try new caps but I think that changing the upper caps would have done the trick too.

[damdam]

Re: Toshiba satellite A200 (non Nec/Tokin OE907) locks up when plugged in.

Tnx for your answer.
Should I orderd 4x 300uf 2.5v ESR 7 mohm case D?
How does ESR reflect on their output?

[fabiog]

Re: Toshiba satellite A200 (non Nec/Tokin OE907) locks up when plugged in.

yes those will work fine the lower the ESR the better, if you see on page 6 of the schematic I uploaded it says that 330 2.5v ESR 7 are what the current caps are using.