Lenovo Legion Y540-17IRH

[Visonix]

Hello, I got a problem with my Lenovo Legion Y50-17IRH, motherboard model fy710/fy714 NM-C531 Rev 2.0

I cannot get it to boot, the white power led lights up for 10-12s, and then resets, it's unable to make post. When I power the motherboard with power supply, it draws 0.034A and there's missing 1.2V on coil.
It randomly boots, usually after removing the power supply and waiting 20-30mins, it boots, but only without SSD installed, it shows that boot failed, and when I got SSD connected, it just shut downs after 10-15secs into post.
When it shut downs, or I press power button for about 10s, the amp draw goes from ~2A to 0.034A making it unable to boot again, with missing 1.2V, so I have to disconnect everything, and I can run it again in 30mins.

Any help what I can measure to check if any component is broken?

[mon2]

Keep the SSD out and try to power up. Does it everytime? With no power, measure the resistance to ground of each and every inductor. Checking if there is a low resistance = shorted part on that power rail. Each inductor is linked to a power rail.

[Visonix]

Keep the SSD out and try to power up. Does it everytime? With no power, measure the resistance to ground of each and every inductor. Checking if there is a low resistance = shorted part on that power rail. Each inductor is linked to a power rail.

Hey, no even without SSD it doesn't boot everytime, but when it boots, it doesn't crash like it does when SSD is in. It boots if I turn off power supply for around 20mins.
I haven't found any shorts, there's a lower resistance around GPU/CPU/RAM but it is not shorted.
I am missing 1.2V on RAM inductor, that shows ~120 Ohm with RAM installed.
3.3V coil = 4k Ohm (when I first touch the inductor it shows ~17k and goes down)
5V coil - 11.3M Ohm
battery coil - over 3M Ohms
1.05V coil - 56 Ohms

When there's no boot (0.034A) BIOS chip gets 3.3V on leg 8

[mon2]

Attach the power adapter. Measure the voltage to ground of the DCin mosfets.

Check the following pins on the BQ charger IC:

ACOK
ACDET
REGN
VCC

Post each measurement.

[Visonix]

ACOK - 3.2V
ACDET - 2.7V
REGN - 5.9V
VCC - 19.7V


PQ201
Drain - 20V
Source - 20V
Gate - 26V

PQ202
Drain - 20V
Source - 20V
Gate - 26V

Earlier I have measured PQ601 and PQ602
PQ 601
Drain - 20V
Source - 3.3V
Gate - 3.3V ( was 3.7V when it "booted" to no boot option menu)

PQ602
Drain - 3.3V
Source - 3.3V
Gate - 0.19V ( Was 1.9V when it "booted" to no boot option menu)

[Visonix]

I have changed PU1401 as a lucky guess as it's making 1.2V, but it's still acting the same, even a little worse, it doesn't boot anymore now, it just draws 0.034A from my bench supply, clicking power button doesnt change the amp draw. Is there anything I can check?

[mcplslg123]

Check whether you have 1.8V present or not

[Visonix]

Check whether you have 1.8V present or not

PL7401 - 1.8V
PL7402 - 0V (12.9 Ohms)
PL2101 - 1.09V
PL602 - 3.3V
PL601 - 5V
PL1401 - 0V (137 Ohms with RAM installed )