HP SPECTRE X360 Convertible Model 13-ae019nl motherboard DA0X33MBAF0 rev f. no power

This Laptop doesn’t turns on.
Connecting PSU voltage on connector 20V but after 5 second drops down to 0V and soon increase 20V again and goes on continuously.
I can’t find schematic I didn’t find any clear short and no components become hot.







Coils with resistance to ground of 43K ohm are shorted each other

Hello!

What's the power consumption (in mA) of the board within 5 seconds, when the voltage is 20V?

0,015 A




I checked voltage of 5V on coil marked 5V for 4 o 5 seconds but the coil of 3,3V ? ( I suppose) reach 0,5V and then 0V.

Measure the voltages to ground on pins 1, 2, 9, 11, 12, 14, 17 of the chip located next to the 3V coil.

1= 1,5V for less than 1 second
2= 12,6V
9= 0V
11=2,9V
12=3,3V first on= less than 1 second
second on 3,3V 2 seconds and go on same way
14=0,5V less than 1 second
17= 0,5V first on 0,5 less than 1 second
second on 0,3V for 2 seconds and go on same
way

All other voltages stay on for 3 seconds

Measure the resistances to ground on pins 14, 17 of this chip.

14 = slowly up to 16K ohm
17 = 4K ohm

Replace this chip. It's SY8286BRAC.

Hello
After replacing SY8286BRAC led near dc connector turns on but SY8286BRAC becomes hot and after 10 seconds led turn off.
I have no try again to avoid chip damage I can’t find any short near.

Please, post a clear picture of marked area of the board.

Measure the resistances to ground on points A, B, C, D.

A= rise up to 40k ohm
B= rise up to 230K ohm
C= 3k ohm
D= 4k ohm

Remove this chip SY8286BRAC from the board and inject 3.3V from the laboratory power supply to the point "D". Limit the current to 1A.
What electrical current flows from the laboratory power supply during the test?

0,33 A

This power consumption is too high.
Leave the laboratory power supply connected for about 10 minutes to allow the temperature to stabilize and check which component on the board gets warm.

There is not a hot component, only a little warm on CPU and DDR zone

valieromarco ha scritto:warm on CPU

Are both cores warm, or just a small one?

Are you sure the onboard RAM area is also warm?

Only component clearly warm is CPU because I touch it over, but all area around CPU become a little warm but all very little warm.

The APU hybrid is damaged almost for sure.
To make 100% sure, remove the APU from the board and repeat the test from post #14.