Toshiba A665

[Stevedb]

Hi everybody

Yesterday is my toshiba A665-14c fall out when my stepson was Watching movies on youtube.

Now will the notebook not start up. I have only power light when i push the power button. The light wil go on from the power button. Battery light and powerplug light but no fa no hdd.

What can I do to fix the nootbook. Is this hardware or a software problem.


Please help me

[techman1025]

Re: Toshiba A665

HI
Start by pulling memory out and resitting it. see if it start also fine another power supply to test it also. Start dare .

Techman1025

[Stevedb]

Re: Toshiba A665

Hi i tried the memory but doesn't help . Hdd remove doesn't help also.

On battery alone he is total dead. Battery removed also doesn't start. Another power supply doesn't help also.

Please help.

Regards

Steve

[BlueMidnight]

Re: Toshiba A665

The power button light is turning on, so that seems to mean it is in the S0 power state. But then nothing happens after that (no HDD activity, etc). So that brings up a lot of questions. Is it a CPU problem? EC problem? Firmware problem?

But you also mentioned something else. I'm not completely sure I understand what you were saying though. There are 3 possible configurations of the power sources: AC, Battery, and AC+Battery. Are you saying it does not behave exactly the same in all those configurations? If so, that may give a hint about what to inspect.

[Stevedb]

Re: Toshiba A665

Hey bluemidnight

I mean when i try on battery. I have no power light nothing. When i removed i have power light and on light for 5 sec then nothing. If you want i make pictures. What strange is my stepson was watching youtube on power plug in and shuts suddenly out.

Regards

Steve

[Stevedb]

Re: Toshiba A665

Hi bluemidnight

Pictures with battery and whitout battery . With only battery no lights total dead then

[Stevedb]

Re: Toshiba A665

The other picture

[Stevedb]

Re: Toshiba A665

Nobody has an idea? Whatthe next step is to try.

[techman1025]

Re: Toshiba A665

ok pull out the board apply power see if any of them big Square coils have power like alway on voltage 3.3v or 5v don’t press power button if yes start with bios & EC firmware .
Techman1025

[Stevedb]

Re: Toshiba A665

Hi Techman

Thanks I will try it in the weekend.
Bios firmware and EC firmware where do i found that.

Sorry i am no expieranced in this repair bu I like to learn a lot.



Regards

Steve

[Stevedb]

Re: Toshiba A665

Hi

I saw i got waterdamage on pu2 i removed waterdamage and musure on pu2 2,8 v
Bios battery 0,67. Battery and on pj5 0v and on pq8 pin1 8,6

The waterdame coms from my stepson salvita.

What is the next step. Please help or is the laptop not repairable.

[BlueMidnight]

Re: Toshiba A665

0.67V is certainly too low for the battery. Is that 2.8V on pin 2 or pin 3 of PU2?

But all the other voltages are too low as well. So, let's just start at the beginning. When using AC power, what are the voltages on PQ7 and PQ8 (source, drain, and gate for each)?

[Stevedb]

Re: Toshiba A665

Hi Bluemidnight

Thanks a lot for helping me again. I want be gratfull we can repair the laptop because that is only thing my stepson has. He is sitting in weelchair.

So I measure on pu 2 pin 1= 0v (ground) , pin 2 (4.32v) and pin 3( 2.16v)

Pq7 s(pin1) =19,54v g (pin 4)=8,32V en D=19,54v
Pq8 S=19,54V , G=8,32V en D=19,54v

I think G=8,32V

The bios battery is recharggeble must i order a new one?

Thank you for helping me.

Greetz steve

[BlueMidnight]

Re: Toshiba A665

Okay, PQ7 and PQ8 are good. You originally wrote 8.6V on pin 1, but it was pin 4. So that's perfectly fine.

There is a problem at PU2 however. Pin 3 (the output) should be 3.3V. Pin 2 (the input) must be at least 6V for it to even work properly. In reality, this circuit will provide PU2 with a little less than either main battery voltage or AC adapter voltage (if plugged in).

Either PU2 is not being giving the right voltage, or it has an internal/external low-resistance path to ground.

So, next measure the pins on PQ1, PD2, and PD3. And make sure there isn't any more spill damage in that area.

[Stevedb]

Re: Toshiba A665

Hi bluemidnight this are the new measurements

Pd2 A=19,33V , K=17,96V pq1 =15,98V ,2=2,82v, 3=15,6V
Pd3 k=15,93V en A=0,73V

THANKS

[BlueMidnight]

Re: Toshiba A665

PD3 pin 1 and PQ1 pin 3 should have the same voltage because they are connected together. I assume that's a measurement error or a typo. And because PQ1 should be on (2.82V on the gate), they should all be pretty much the same voltage as PQ1 pin 1.

So, if the ~15.9V values are correct, then the parallel resistors PR9/PR10 are passing a total of (17.96V-15.98V)/34ohms = ~ 58mA.

But... (assuming PU2 pin 2 is still 4.32V)... the series resistors PR11/PR17 are passing only (15.93V-4.32V)/400ohms = ~29mA. That's high. But also, where is the other half of the 58mA going? There are no other paths that should be drawing that much current.

Most likely problems:
- Conductive spill residue hiding somewhere (maybe even underneath a component)
- Bad PU2, PC10, PC12, and/or PU1 (connected to PQ1 via point labeled "N1" on the schematic)
- Bad component somewhere on +CHGRTC/+RTCVCC

The voltage on PQ1 pin 1 should be at least ~18V. You can simply try removing components until the voltage stops sagging so low. That will narrow down where the problem is. There might be one problem, or there might be more than one.

What I would probably do is just remove PQ1 and PU2. They are right next to each other and can both be removed with a single heating (assuming you have a hot air station). Then check the voltage on PQ1 pin 1 (the pad where it was) to see if it is okay. If so, reattach PQ1. Check pin 1 voltage again. If still okay, then problem is PU2 or something on its output. If not okay, then problem may be PU1. Etc, etc.

[Stevedb]

Re: Toshiba A665

Hi bluemidnight
i removed pu2 then I got on PQ1 pin 1=18.43v , pin2=18,43v and on pin 3= 3,3 v i supposed this it good
I put pu2 back same result then i removed pc 11, pc12, pc10 i do not find. pu1 same result. So i supposed pu2 is defect(bad). Is my concludion good?
greetz Steve.

What abouth the cmos battery must it also be replaced

I

[BlueMidnight]

Re: Toshiba A665

When you say you "put pu2 back same result", do you mean that PQ1 pin 1 dropped back down to 15.9V again, etc? If so, then yes, PU2 is likely bad.

With PU2 removed, you can test the resistance to ground on +CHGRTC just to make sure there's no short drawing too much power from PU2. If not, then PU2 is the culprit.

The CMOS battery might be just fine. PU2 is responsible for charging it. With PU2 bad, the battery would have been forced to provide power to the +RTCVCC rail until the battery died. On the other hand, if you have to order PU2 then it might make sense to order both. That's up to you.

[Stevedb]

Re: Toshiba A665

Hi bluemidnight

That is what i mean that the voltage drops. And that the voltage not be steady. That is the reason why different voltage i measured. The voltage flutuated.

Can i use another component for replacing g920at24u_sot89-3 .

Regards

Steve

[Stevedb]

Re: Toshiba A665

Hi bluemidnight

I had donorboard my sister laptop chassis LA532p
So i raplaced pu2, pq1 and pd3. The were the same components.

I got sill on pq1 pin 15,96v and on pu 2 pin3= 2,14v.

I removed pu1. That was the same result.

What will be the next step