Sony SVF15N DA0FI3MB8E0 no power on

[zolie]

Hello,

I would like to repair this motherboard. Can you help me with this? I have little experience. Thanks!

PQ34
1-2-3: 19.5V
4: 19.5V
5: 0V

[mon2]

Re: Sony SVF15N DA0FI3MB8E0 no power on

Try this first:

https://www.badcaps.net/forum/showthread.php?t=65831

[zolie]

Re: Sony SVF15N DA0FI3MB8E0 no power on

Try this first:

https://www.badcaps.net/forum/showthread.php?t=65831

I tried. Not good.

[Dreigas]

Re: Sony SVF15N DA0FI3MB8E0 no power on

Hello,

I would like to repair this motherboard. Can you help me with this? I have little experience. Thanks!

PQ34
1-2-3: 19.5V
4: 19.5V
5: 0V

I had the same problem...

Check PQ35 if is not shorted and PR151, PR152 have 220k ohms.

to PQ34 gate (4) should be presented ~10V, not 19.5V

[mcplslg123]

Re: Sony SVF15N DA0FI3MB8E0 no power on

Remove PQ35 and check pin4 of PQ34 again. The problem is sony's classic protection

[Dreigas]

Re: Sony SVF15N DA0FI3MB8E0 no power on

Maybe someone has some ideas for this motherboard...

I had the same exact problem, I changed PQ34 (because was shorted) and now the main power rail 19V is ok, LDO is presented, and the battery can be charged too.

Then I plug the adapter it takes 0.004A(LDO, 3V and 5V are ok then, but only for a few seconds), after pressing the ON button 3V and 5V are presented again (Amps ups for a short time up to ~0.015A), and don't disappear, but no other power appears, like for CPU, RAM and etc, only LDO, 3V and 5V works. I don't found any more shorts. Anyone have some ideas?