Sony MBX 247 Laptop Dead. Need help ( Pics attached )

[IamPritesh]

Re: Sony MBX 247 Laptop Dead. Need help ( Pics attached )

I am overwhelmed by the support you guys are providing here. Amazing.

I did change the capacitor with the exact value but the MB is still dead.

Why do I get a(minus) -3.3 volt on one end of the capacitor PC61 even though I am using the probes correctly ?

[IamPritesh]

Re: Sony MBX 247 Laptop Dead. Need help ( Pics attached )

Anybody please help.

[on/off]

Re: Sony MBX 247 Laptop Dead. Need help ( Pics attached )

Maybe need replace PD27, PD28, PC61, PC62, PC68, and PC69

[IamPritesh]

Re: Sony MBX 247 Laptop Dead. Need help ( Pics attached )

Maybe need replace PD27, PD28, PC61, PC62, PC68, and PC69

Also I do not see any led glowing when I plug in the the adapter. What signals should I check.

I remember before opening the laptop, when I plugged in the charger the battery orange light would glow. ANd on pressing the power button the the green light would glow till the button is pressed.

right now no leds glow in any circumstances. ALso what causes a negative voltage on PC61 ?

[on/off]

Re: Sony MBX 247 Laptop Dead. Need help ( Pics attached )

Did you compare your measurement, before-after replacement?

IMO:
Basicly PD27 and PD28 are pump (Come from 5V, should be impossible reversed ) the 5V kicked by oscillation via PC66 and PC69 by 3V_DL. the pumping increase little by little via diode to other diode.

Datasheet will better for explanation

Maybe need replace PD27, PD28, PC61, PC62, PC68, and PC69

Should be PC66 not PC68

[IamPritesh]

Re: Sony MBX 247 Laptop Dead. Need help ( Pics attached )

Did you compare your measurement, before-after replacement?

IMO:
Basicly PD27 and PD28 are pump (Come from 5V, should be impossible reversed ) the 5V kicked by oscillation via PC66 and PC69 by 3V_DL. the pumping increase little by little via diode to other diode.

Datasheet will better for explanation



Should be PC66 not PC68

No I did not take any measurements before removing the capacitor. There was a physical burn not and it showed shorting so I simply removed it.

Is this section and diode anyway responsible for not letting the LED glow when AC adapter is plugged in ? ACIN signal is present on IO ChiP but AC_PRESENT signal is missing. Just thinking if I am missing something.

[on/off]

Re: Sony MBX 247 Laptop Dead. Need help ( Pics attached )

If board normally +15vpcu not going to any drain mosfets 2n7002, cause all trigger still OFF (S5_ON, RUN_ON) as state DISCHARGE.

May be need to check all 1Mohm resistor that connect to +15vpcu as well.

[IamPritesh]

Re: Sony MBX 247 Laptop Dead. Need help ( Pics attached )

Update : Removing PD28 from the board helps get rid of reverse voltage of -3.3Volt on PC61.
Do you PD 28 could be the cuplrit ? ALso I am unable to find a replacement for the same. I can it is a Schottky diode . What other options do I have now other than finding the same model diode ?

[on/off]

Re: Sony MBX 247 Laptop Dead. Need help ( Pics attached )

Mostly those of them found on donor board. (especially quanta mobo)

Part++++Vendor++++Marking

CHN217 [Chenmko-A7]
1PS302 [NXP-Ct3]
BAT54S [Fairchild-L44]
BAT54SW [Diodes-KL8]
BAT54SW [NXP-44]

[IamPritesh]

Re: Sony MBX 247 Laptop Dead. Need help ( Pics attached )

Mostly those of them found on donor board. (especially quanta mobo)

I managed to find BAT54S-7-F_SOT23-3 in one of the donor board. The package is slighly smaller than the one that was removed. You think this could work ?

[on/off]

Re: Sony MBX 247 Laptop Dead. Need help ( Pics attached )

I managed to find BAT54S-7-F_SOT23-3 in one of the donor board. The package is slighly smaller than the one that was removed. You think this could work ?

Good idea is read datasheet first.

I think that problem only doesn't fit with pad of diode.

If you don't mind please mention list your donor board. Easily found part on schematic first than search to real board.

[IamPritesh]

Re: Sony MBX 247 Laptop Dead. Need help ( Pics attached )

Good idea is read datasheet first.

I think that problem only doesn't fit with pad of diode.

If you don't mind please mention list your donor board. Easily found part on schematic first than search to real board.

I have 6-7 donor board and none of them has the one that matches diode. (Checked with the schematic)
BAT54S
BAT54C
they are all different designs.

Can we use a wire jumper or something just to check if this board can start ?

[on/off]

Re: Sony MBX 247 Laptop Dead. Need help ( Pics attached )

I think that problem only doesn't fit with pad of diode.

If your donor was smaller than broken part, solder leg of 3 on original pad, a pairs of legs with help wires to each pad.

If you don't mind please mention list your donor board. Easily found part on schematic first than search to real board.

What I mean, make list mainboard ID of your donor board, I'll share a few boardview what I have. helps you more easily find component where is the location on mobo.

In example, Quanta ZQE, ZQ9, ZE7 (a few of my donor list)

[IamPritesh]

Re: Sony MBX 247 Laptop Dead. Need help ( Pics attached )

If your donor was smaller than broken part, solder leg of 3 on original pad, a pairs of legs with help wires.



What I mean, make list mainboard ID of your donor board, I'll share a few boardview what I have. helps you more easily find component where is the location on mobo.

In example, Quanta ZQE, ZQ9, ZE7 (a few of my donor list)

About donor being smaller , actually it was for discrete board so it is not mounted I misread the schematic

Here is the list of donor boards I have

LA-910P
La-4031
R13_UMA ( HP G6)
LA- 5752
HPMH-41-AB6200-D00G

These are the only donor boards I have with me.

[on/off]

Re: Sony MBX 247 Laptop Dead. Need help ( Pics attached )

Hmmm...I think only HPMH-41-AB6200-D00G have those diodes.

Haave looking PD8 and PD7 at Top motherboard. If same code LD3

https://www.eevblog.com/forum/repair...;attach=237731

[IamPritesh]

Re: Sony MBX 247 Laptop Dead. Need help ( Pics attached )

Hmmm...I think only HPMH-41-AB6200-D00G have those diodes.

Haave looking PD8 and PD7 at Top motherboard. If same code LD3

https://www.eevblog.com/forum/repair...;attach=237731

OK I replaced them and now I have around 10V on 15VPCU line . No more reverse voltage but still no sign of life.
I also notice that PQ59 Pin 4 has only 0.3 volt . Is that normal ?

[Techtiger]

Re: Sony MBX 247 Laptop Dead. Need help ( Pics attached )

[QUOTE=IamPritesh;877776]OK I replaced them and now I have around 10V on 15VPCU line . No more reverse voltage but still no sign of life.
I also notice that PQ59 Pin 4 has only 0.3 volt . Is that normal ?[/QUOTE

If board normally +15vpcu not going to any drain mosfets 2n7002, cause all trigger still OFF (S5_ON, RUN_ON) as state DISCHARGE.

May be need to check all 1Mohm resistor that connect to +15vpcu as well.

there is a Voltage drop 10VPCU it should be 15VPCU

[IamPritesh]

Re: Sony MBX 247 Laptop Dead. Need help ( Pics attached )

OK I replaced them and now I have around 10V on 15VPCU line . No more reverse voltage but still no sign of life.
I also notice that PQ59 Pin 4 has only 0.3 volt . Is that normal ?

there is a Voltage drop 10VPCU it should be 15VPCU

Which component could be resposonsible for the volrage drop ?
When I mount the PD27 then I get around 7.5 volt on pin 3 and then i mount PD28 then I get 9.9 volt on Pin 3.

Also is the gate voltage on PQ59 correct ?

[Techtiger]

Re: Sony MBX 247 Laptop Dead. Need help ( Pics attached )

PD28 in put voltage 15V and out put voltage 9.9V ? voltage in PU9 pin27 & resistance in PL13?

[IamPritesh]

Re: Sony MBX 247 Laptop Dead. Need help ( Pics attached )

PD28 in put voltage 15V and out put voltage 9.9V ? voltage in PU9 pin27 & resistance in PL13?

PD27 Input Voltage - 5 Volt
PD28 Output Voltage - 9.9 Volt
If i remove the PD 28 then output voltage of PD27 is 7.5 . Hope it a bit clear now

Voltage on Pin 27 of PU 9 is 4.68.

Any further help is appreciated.