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Скажите, пожалуйста, DC_IN + точка и второй DC_IN + точка в схеме, они связаны вместе, как нарисован? Если да, то после R19 Следует R33 и L1?

do not use goodle translate. Never.
What is your problem? Type your laptop code name correctly.

Ok, thanks for advice.

Its a MSI U100 With N01 11 Ver 1.0 MOBO.

Problem is that its not power on, no standby Voltage.

Voltage at DC_IN+ Unstable, jumping all time from 0 to 5v.

Checked DCIN+, no short.

I moved slowly from DC_IN+ and checked components till I found - when remove R19 the voltage stops jumping ,are stable and DC_IN at max are 20.40V, like it should be.

Then Put back R19 (Voltage start jump around) and remove L1 next to him, but this did not make any changes.

Checked other component around to R19 but they seems to be ok.

That means short circuit. So the supply is trying to set the proper voltage but protection system in the supply is switching off the load.

That confirms what I said. Now check all transistors are not to be in SC. First of all - Q41

Removed Q41 no changes, Do I need to remove them from MOBO before check, and how to check ?

For superficial analysis you may check them on MOBO. If a transistor seems to be shorted
just unsolder the side of mosfet with "gate" pin - from 1 to 4 and check it on mobo. Be sure that is a single transistor in a chip.
Otherwise you should unsolder it from MOBO fully and check it apart. See the scheme if it`s coupled.
Set your tester to diod measuring position and check the transistor not to be SC`ed.
Depending on polarity you can open the transistor by touching the gate with "-" probe of the tester or "+" .

example Diode Mode Q40 Transistor where 1,2,3=S. 4=G. 5,6,7,8=D

- to 1,2,3 and + to 5,6,7,8 legs readings = 0.495V

+ to 1,2,3 and - to 5,6,7,8 legs Readings = 0

- to 1,2,3 and + to 4 Readings = 0

+ to 1,2,3 and - to 4 Readings = 0

-to 5,6,7,8 and + to 4 Readings = 0


How it should look to be Shorted ?

If its unsoldered and has these readings it IS shorted unless you opened it with touching the gate leg.
Here is the example of normal readings:
- to 1,2,3 and + to 5,6,7,8 = 0,495 ( this means you measure diod transition inside)

+ to 1,2,3 and - to 5,6,7,8 Readings = inf

- to 1,2,3 and + to 4 Readings = inf

+ to 1,2,3 and - to 4 Readings = inf

-to 5,6,7,8 and + to 4 Readings = inf

One of the combinations is opening the gate leg so the mosfet appears to be shorted.
Inversed combination is closing the mosfet.
BTW don`t forget to press "thumb" icon on the right side of a message to thank somebody.

It will take ages to desolderandcjheck each transistor.

I connected 12V and realised that Q12 wihch contains Q12A and Q12B of schematic drawings, gets very hot. I removed and now 20.40 Voltage is stable.

I check Pins under Q12

Voltage

1=0v
2=0v
3=0v
4=20.40v
5=0v
6=0v
7=20.40v
8=20.40v


I noticed that 1 and 3 leg have shorted with ground, resistance 6ohms, it should not be like that, because drawings show it is PWR_SRC ?

You didn`t get it. At short glimpse you should check them right on the MOBO soldered.
And if you see the resistance is very close to 0 Ohm so you are to unsolder one side of a mosfet and check it then.
So you will save your time. Most of faulty mosfets are getting burnt to zero resistance.
So you may be sure that the most of issues concerning transistors are located by this method.
Besides no need to unsolder most of coupled mosfets fully cos the rest of soldered legs are not impeding to measure the impedance )).

Sure

I was checking components moving closer to shorted component and found that Q41 fourth leg is ground and its shorted.

I changed for new one Q41 sp8k10s transistor, checked - no shorts anymore, then plugged charger in, Q41 became hot and shorted again.

Removed and checked - its dead.

What Can cause them to die and what I have to look for ?

Update :

Q41 area getting 20.40v from pin 1

I have MAX 8724 removed and for DCIN, CSSP, CSSN, = 20.40v

power button switch have 2.65v

U16 VIN - 2,67

Everything looks good without Q41

Sorry for the delay, been busy.
Have you replaced the MAX with new one? Or just removed it?
It`s obvious that is dead.
Oh, of course, if you removed the MAX and not set new one and left the mosfet gate leg free so it may cause to die this mosfet and the rest of the scheme.
Mosfet can be undriven cos the gate leg is not connected so whole 20V goes thru opened mosfet and burns all on its way..
Now, unsolder one side of choke1 and check the resistance of the rest of the scheme.

Max is removed at all.

Q41 Removed.

Choke one leg desoldered

Sorry mate, but what exactly I have to look for ?

Some reading just for case,

Q40 S=20.40v, D=20.40v, G=8.6v

Q5 C=8.5v, B=20.16v, E=20.40v

Q6 D= 20.14v, S=0v, G=0v

do you mean to check resistance between ground an various points on mobo ?

There is no need to give me those readings.
First of all you should check the resistance between ground and soldered choke leg.
If the resistance is close to zero and this means you should look for the next burnt element.
If not, you should solder new MAX and new Q41.

Q41 in studio

There are no shorts, readings are 0.L in ohm mode or 0L. in continuity mode

I soldered Max back and replaced NN-SP8K10S_ (Q41), no short anymore, no heat, Perfect !

God bless you mate, Thanks !

I still miss one NN-SP8K10S which i removed from same motherboard to check your solution as I burned out all spares :D, wait for it from china and then I`ll reply back about mobo startup !