Toshiba l40-17s martwy

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Toshiba z odwrotnie podłączonym zasilaczem (spalona dioda d4101).
Usunąłem szczątki diody ale sprzęt nie reaguje. Ciągnie ok 20mA (czyli norma) ale brak jakiejkolwiek reakcji na power on.
5V jest 3.3V też. Do włącznika dociera 3.3V i spada do zera po wciśnięciu switha (to samo na nóżce 2 U2901) Teoretycznie powinna wystartować i nic...

Udało mi się ją odpalić odłączając baterie CMOS i podając mu sztrum ale "głucha cisza" ekran czarny (ciągnie wtedy 1,3A, CPU się szybko nagrzewa) napięcia pojawiły się prawidłowe na reszcie dławików.

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If all the other voltages are there, this coud be KBC - IT8511.
Check the power sequence and complete set of voltages:

Serg0 написав:If all the other voltages are there, this coud be KBC - IT8511.
Check the power sequence and complete set of voltages:

So IT8511 exchange should help?

Check pin48 of IT8511. There must be high level

And then, if you press POWER button, signal should come to pin2 of IT8511

pin48 = 3.3V

Do you have +12V on pin 5 of PU5101?

I can't find this component

It is small 5-pin IC, SOT23-5 case. Looks like a transistor with 2 extra pins

PU5101 is a marking on the PCB? None of the "SOT23-5 'element has such sign

-- piątek, 19 listopada 2010, 00:38 --

Sorry I found on PCB text, it is TERESA20 REV2.2

Aha, there is a problem!
Schematic for this board is not available. But it is not that bad - I have 2 such working boards in workshop. I can give you some hints later. In general, schematics are the same, only numbers of elements are different.

-- Friday, 19 November 2010, 13:07 --

Have a look on U8100 for +12V

U8100 I can't find, In what area to look it up?

Look at the picture, thanks for it to oneeye!

pin1-3,27V
pin2-0V
pin3-19V
pin4-12V
pin5-1,23V

So, very good!
Remember pin 4 and check voltages on the same pin of other ICs in same case around. Please report them here!

I checked the pins on the opposite

It should be
pin1-19V
pin2-0V
pin3-2,5V
pin4-1,3V
pin5-12V

All others are the same on pin 4 with the exception u2101 - pin4 = 0V

There must be 1,25V. Seems to me - it has to be replaced! If you have signal on Enable pin(number 3), of course!

Every pin on U2102 is 0V!

Check resistance from ground to pins 1 and 5

pin1 - 9kOhm
pin5 - 26kOhm

If you press power button, what happening with volage on pin 1?