LA-F115P +19VB = 13.6v instead of 19v

[koby058]

Hi

I getting 13.6v instead of 19 on this board

I have measured D1 of PQB02 (AON6994) and getting same 13.6

I dont know how to test those Dual Asymmetric MOSFET

Can you please help me understand which IC is failing ?

attached link to schematic and boardview

https://www.badcaps.net/forum/showth...light=la-f115p

[mon2]

Re: LA-F115P +19VB = 13.6v instead of 19v

Do you have 19V at the adapter level ?

Is the battery connected ?

What is the voltage of the battery at the battery connector ?

[mcplslg123]

Re: LA-F115P +19VB = 13.6v instead of 19v

13.6V is very likely correct as NVDC is involed here.

[koby058]

Re: LA-F115P +19VB = 13.6v instead of 19v

HI,
yes 19v present in the adapter level
battery not connected.
I dont have the batt near me at the moment

[koby058]

Re: LA-F115P +19VB = 13.6v instead of 19v

13.6V is very likely correct as NVDC is involved here.

the laptop fan turns on for a second and then stopes. there is no post.

when the power button pressed, i see about 0.8v in PLI01/02 and around 0.9 on PLV01/02.

I get hit from CPU.

Can you guys please suggest another test direction ?

[rediii]

Re: LA-F115P +19VB = 13.6v instead of 19v

the laptop fan turns on for a second and then stopes. there is no post.

when the power button pressed, i see about 0.8v in PLI01/02 and around 0.9 on PLV01/02.

I get hit from CPU.

Can you guys please suggest another test direction ?

did you try another original charger?

[koby058]

Re: LA-F115P +19VB = 13.6v instead of 19v

13.6V is very likely correct as NVDC is involed here.

Thanks
I will have one in the evening, when i will get it i will test

[koby058]

Re: LA-F115P +19VB = 13.6v instead of 19v

13.6V is very likely correct as NVDC is involed here.

Just to understand you, even though it says 19v in schematic and i have 13.6 on this coil (PLV11) it is still reasonable ?

[mon2]

Re: LA-F115P +19VB = 13.6v instead of 19v

Correct.

https://en-support.renesas.com/knowledgeBase/6680047

[koby058]

Re: LA-F115P +19VB = 13.6v instead of 19v

tried with another good charger still same.
voltage on bat 11.3v
I can also see that the capslock is always on

[rediii]

Re: LA-F115P +19VB = 13.6v instead of 19v

tried with another good charger still same.
voltage on bat 11.3v
I can also see that the capslock is always on

if no suspicious measuring occurs, try a known good bios

[mcplslg123]

Re: LA-F115P +19VB = 13.6v instead of 19v

You beleive it or not but 13.6V as main rail is correct. You are getting vga core/cpu core and thats a good sign.

On page3/4, you have all the rail listed. Find out what is missing.

What is the consumption on your dc supply
01.When off
02.When turned on with ram stick
03.When turned on without ram stick.

[mcplslg123]

Re: LA-F115P +19VB = 13.6v instead of 19v

Yes, flash known good clean me bios as@rediii has suggested.

[koby058]

Re: LA-F115P +19VB = 13.6v instead of 19v

Hi

I have tried bios and got the same results.

https://www.badcaps.net/forum/showthread.php?t=112763

Any other suggestion ?

[Sephir0th]

Re: LA-F115P +19VB = 13.6v instead of 19v

Share exactly what voltages you get in the short time where the board is on, each coil. Also resistance to GND of all coils.

Also pay attention to what testing methods the other member have shared here. Mcplslg123 has already told how to proceed.

[mcplslg123]

Re: LA-F115P +19VB = 13.6v instead of 19v

The problem with most of the members here is that they just want a readymade solution to their problem. They dont want to struggle it out. When your efforts are half baked, results will be not on expected lines.

Honestly, sometimes i dont feel like suggesting anything.

[koby058]

Re: LA-F115P +19VB = 13.6v instead of 19v

Hi,

I am sorry you feel that way, actually i am willing to put the effort but as a newbe on this area it is sometimes can be a bit overwhelming and some times you feel like you even don't know where to start. so i would like to thank you for your suggestions and help and also i understand you side.
Sepfiroth I will try what you and mcplsg123 suggested and post back

[koby058]

Re: LA-F115P +19VB = 13.6v instead of 19v

Let me share what happened today.

I started my work place dell laptop and saw that the caps lock is turning on for a few sec so i thought may be it is a screen issue, so i have connected it to external monitor and it booted. so you where right from the beginning.

Now it is complaining it does not recognizing the adapter power i will test to see if adapter signal is there and will post here

[mcplslg123]

Re: LA-F115P +19VB = 13.6v instead of 19v

Nice to know that the unit is working. Try with another dell original known good adapter.
If adapter is still not recognised, you have alikely fault in PS_ID circuit which is very simple to solve. Check whether PS_ID is present on pin36 of SIO and 33 Ohms resistor is intact or not.

[koby058]

Re: LA-F115P +19VB = 13.6v instead of 19v

Will take me time, i will check and notify here, thanks a lot