Toshiba Satellite C850-B720 no power - schematic

[fddizon]

hi,

does anyone have schematic of this mobo?

PLF/CSF 45W UMA & DSC MB
REV 2.1


TIA

[aanan]

Re: Toshiba Satellite C850-B720 no power

shematic
https://www.badcaps.net/forum/showthread.php?t=35111

[fddizon]

Re: Toshiba Satellite C850-B720 no power

aanan,

thanks for the link.

Laptop now works.
Found 2nd FET shorted. replaced and laptop turns on using DC bench supply.
when i used the charger laptop quickly died. ???$$##??

i noticed charger was repaired recently and i suspected something wrong with it so i checked the output and found out that it was reversed polarity...

replaced the FET again and corrected the polarity of the charger made the laptop and charger works normally.

[edgars_ab]

Re: Toshiba Satellite C850-B720 no power

Hey fddizon, yesterday i got the same laptop with a very same problem, like you had. I suspect it has suffered from charger with reversed polarity as well, but unfortunately i'm not so techy with finding these fets, as i'm still learning to solve problems on such a low level. Was it this one? (just a guess)

https://cdn.badcaps-static.com/pdfs/...c46783c0ed.pdf

If not, could you give me a part number, or a marking on the circuit board, which mosfet was shorted? Thanks!

[yaman]

Re: Toshiba Satellite C850-B720 no power

Same problem with a C855, I will try to replace the mofset.
How did you reverse the polarity of the charger ? Did you just reverse cables ?

[fddizon]

Re: Toshiba Satellite C850-B720 no power

yes,

thats what i did. reverse the cables from the pcb.

[fddizon]

Re: Toshiba Satellite C850-B720 no power

yaman,

yeah it looks like that. so tiny that i cannot read the part number.

[yaman]

Re: Toshiba Satellite C850-B720 no power

Mofset switched but still no power, 19v in 1v out.
1 V also for the battery, I don't think it's charging with this voltage.

[passete]

Re: Toshiba Satellite C850-B720 no power

hi,

does anyone have schematic of this mobo?

PLF/CSF 45W UMA & DSC MB
REV 2.1


TIA

I'm searching for bios and ec for this mobo PLF/CSF 45W UMA & DSC MB, i have no power/lights.
Strange thing, is that some components get warm, like coils, pch once i connect the PSU.
Thanks