Lenovo Slim Pro 7 14ARP8 83AX No Power

[SoulFreeze]

Hello All, I have a Lenovo Slim Pro 7 14ARP8 83AX, Board No NB6369A_MB_V5

Behavior - Pressing power button results in three second led blinks on the button,
Connecting charger lights up orange as normally would while charging.
Connecting charger without battery blinks orange.
No fanspin.

Tried flashing bios, no change.

I inspected the board and found a burnt component on the USB / Power button daughter board. I assume the comonent was an esd protection diode as it was on the USB A port power rails. removed the component but still exhibits same behaviour (5v is present on the usb)
I can measure 20v on various parts of the board, but no power on any of the power inductors for GPU / CPU
I observed that if i disconnect the daughterboard ribbon cable one fan spins at high speed otherwise still no boot or power to gpu/cpu.
I also measured really low resistance, (around 0.2 ohm) on the GPU inductors, but i have read that that is typical for GPUs?

Not sure where to head from here as i have no access to schematics. any pointers would be appreciated.

Will post further findings in case of any new development

[SoulFreeze]

Did some further digging, Found a short on this component, Marked CWFEVA, some sort of DC-DC converter. Cant find datasheets, anyone have a clue what it is?

[mon2]

Attached.

Silergy CWF*** - SY8883DFC

[SoulFreeze]

Attached.

Silergy CWF*** - SY8883DFC

Thank you very much. removed the chip and the short on the inductor is gone, placed an order for the chip, so might be a while till i post any updates. Wondering if there is a simple way to temporarily apply power to the rail to do test in case i need more components, Or just wait for the chip?

[mon2]

Wait for the chip. Bypass / hacks are rarely worth the risk. Aliexpress is usually quite fast these days. We are receiving packets in under 2 weeks to Canada. You may be able to find the same from a donor board / ebay, etc. but most are vendors out of China.

[SoulFreeze]

Took a bit of a break, Managed to install the chip, laptop booted up and works fine, only issue is with audio now. speakers work but only the bass speakers on the bottom of the unit, not the front ones one the sides of the keyboard resulting in lack of high end, also headphone jack doesnt work, just static/buzzing. thinking it might be something to do with the ALC3306, though im puzzled, isnt it the same chip driving the working speakers? im assuming it has multiple channels and its partially dead?