Where can i find it, 15VPCU

[Life Goes On]

Hi guys

I need to know from where come this 15VPCU,
because i measure 8v in place from the 15v,
but i can find where the 15v supposed to come from,
can anyone tell me, so i can go further with my searching.THX

page 36

[ben7]

Re: Where can i find it, 15VPCU

Sheet/page 32, all the way on the left hand side, about 3/4 the way down. Looks like it comes from there (by the diodes PD6 and PD7).

Also looks like it is some sort of "charge-pump" circuit.

[Life Goes On]

Re: Where can i find it, 15VPCU

Thank you ben7, i didn't see that, but now from that point before PR101 i still got 8v in place of 15v, can anyone see on the sheet where is the point before that or why i have 8v, please.

[ben7]

Re: Where can i find it, 15VPCU

A few things to check:
1. 5VPCU, should (I assume) measure 5V ... be sure to check that. If it isn't 5V, then the problem might be elsewhere ... not in the 15V boosting circuit. (5VPCU can be found on page 32)
2. Check to see if pin 19 of PU2 (page 32) has 5V on it.
3. If you have an oscilloscope, check to see if there is a pulsing signal on PU2 pin 18. It should go from about 0V to 5V.
4. If those are fine, check the diodes PD6 and PD7 (they are dual diodes - two diodes in one component)
5. It could be possible that the +15V is having too much current drawn from it. I haven't looked at all the things connected to the +15V yet. (P.S. Pretty much all PDF viewers have some sort of "find" tool. For me, it is CTRL+F (I use windows). That is how I found where the +15V came from.)

[Life Goes On]

Re: Where can i find it, 15VPCU

Thanks again ben7, let see, starting with point 1, 5PCU on (page 32) is ok,
point 2, pin 19 of PU2 (page 32) the 5v is ok,
point 3, can't do it, i don't have oscilloscope,
point 4, dual diodes PD6 and PD7 is ok,

PD7 have 8v in place of 15v, what is the next step you think, and thx for the CTRL+F it help alot.

[ben7]

Re: Where can i find it, 15VPCU

The only things I see that are connected to 15VPCU are some high value resistors, in the range of 1 megaohm or so. Nothing that could draw too much power.

I do wonder, one or more of the capacitors connected to PD6 and PD7 could be bad. Is it possible that your meter (if it can read capacitance) could check them in-circuit?

Also, check the resistance from PU2's pin 18 to ground.

[Life Goes On]

Re: Where can i find it, 15VPCU

The only things I see that are connected to 15VPCU are some high value resistors, in the range of 1 megaohm or so. Nothing that could draw too much power.

I do wonder, one or more of the capacitors connected to PD6 and PD7 could be bad. Is it possible that your meter (if it can read capacitance) could check them in-circuit?

Also, check the resistance from PU2's pin 18 to ground.

I can read the PD6 and PD7 separately not in string, they both are 1.832 each on capacitance,
and the PU2 pin 18 to ground are 9.6 on resistence.

[ben7]

Re: Where can i find it, 15VPCU

I can read the PD6 and PD7 separately not in string, they both are 1.832 each on capacitance,
and the PU2 pin 18 to ground are 9.6 on resistence.

Oh.. ok. So the capacitors are good then. (I'm assuming 1.832 is 1.832 nano-farads)

The problem looks to be elsewhere, not in the 15V boosting circuit.

9.6, that is 9.6 ohms, right? If so, that is BAD!
PQ25 might be shorted. Also check PQ26 too.
Do you get power on "VIN" and "Vin_17020_5V Vin_17020_"?

[Life Goes On]

Re: Where can i find it, 15VPCU

Oh.. ok. So the capacitors are good then. (I'm assuming 1.832 is 1.832 nano-farads)

The problem looks to be elsewhere, not in the 15V boosting circuit.

9.6, that is 9.6 ohms, right? If so, that is BAD!
PQ25 might be shorted. Also check PQ26 too.
Do you get power on "VIN" and "Vin_17020_5V Vin_17020_"?

Yes it was 9.6 ohms,
on VIN i have 19v and on Vin_17020_5V and Vin_17020_3V i have 19v also.

[ben7]

Re: Where can i find it, 15VPCU

Yes it was 9.6 ohms,
on VIN i have 19v and on Vin_17020_5V and Vin_17020_3V i have 19v also.

Remove PQ25, and see if the short goes away. (Check it with your ohm-meter ... don't attempt to turn the laptop on)

[Life Goes On]

Re: Where can i find it, 15VPCU

Remove PQ25, and see if the short goes away. (Check it with your ohm-meter ... don't attempt to turn the laptop on)

I remove it and no short, do i have to replace it for a new one, or something else.

[ben7]

Re: Where can i find it, 15VPCU

I remove it and no short, do i have to replace it for a new one, or something else.

The best thing to do would be to replace it with the same part, but it might be possible to find a suitable replacement (that can be a lot of work xD).

I think it would be good if you test PQ26 too, if it's shorted it could blow the new FET.

Can't say if replacing it would fix the problem or not, but let's hope.

[Blacktek]

Re: Where can i find it, 15VPCU

what if you check the voltage on both sides of PL6, if 5v present. then ill probably check PQ23 PQ24 out of circuit.
also check how much voltage you are getting on PD6 pin 2.

[Life Goes On]

Re: Where can i find it, 15VPCU

The best thing to do would be to replace it with the same part, but it might be possible to find a suitable replacement (that can be a lot of work xD).

I think it would be good if you test PQ26 too, if it's shorted it could blow the new FET.

Can't say if replacing it would fix the problem or not, but let's hope.

I gone order new one, and try to replace it.

[Life Goes On]

Re: Where can i find it, 15VPCU

what if you check the voltage on both sides of PL6, if 5v present. then ill probably check PQ23 PQ24 out of circuit.
also check how much voltage you are getting on PD6 pin 2.

On both side PL6 i have 5v, but i can see PD6 pin 2, on what page is that.

[ben7]

Re: Where can i find it, 15VPCU

On both side PL6 i have 5v, but i can see PD6 pin 2, on what page is that.

On page 32. Pin 2 of PD6 connects to one side of PL6.

Also, I hope you didn't power it on with PQ25 removed ... O_o

[Life Goes On]

Re: Where can i find it, 15VPCU

On page 32. Pin 2 of PD6 connects to one side of PL6.

Also, I hope you didn't power it on with PQ25 removed ... O_o

On that pin i got 5v, no i didn't power it on, i got alot of voltage that i write down the other days, that s why i know it was 5v on that pin.