Hp envy x360 15-CN Intel core I7-8th gen, power on but no display!

[Ariu]

hello everybody,

I've already opened a topic about schematic for this model but unfortunately I haven't received an answer because schematic doesn't seem to be available.
The problem with the mainboard is as follows, it turns on, but no display.
All power rails seem to be OK, except pl4801.
Can someone tell me how much voltage there should be?(maybe someone has this board).
Boardnr: GALE 4G WHL MB- 18709-2


the story of this was water damage, the area red marked, already cleaned.

[mcplslg123]

PL4801 seems like GFX Core coil. This rail rises under load only and can be measured with DSO only. If you have DSO,
Put your positive proble on PL4801 and then press power button,you should see a slight spike once and goes off. If the behaviour is what i've written,then GFX core is absolutely fine.

This rail is not relevant for posting. Connecta usb keyboard and check munlock light glowing or not? Lets be sure whether the mb is posting or not.

PL4801 voltage will be close to Core voltage ,ie, 0.7V to .0.8V

[Ariu]

Unfortunately no post from mainboard, capslock is not glowing when Keyboard connected…

Another strange behavior that i noticed, is when the battery is disconnected , charging light is flashing after trying to power on the mainboard and also „clicking“ noise .

With the battery conntected and charger plugged in mainboard is starting fine but no post.

[Ariu]

Blown resistor at water damaged area near GPU section caused the Laptop to no post.
Resistor replaced (100k), Notebook is posting and showing picture!
we have pictuuuure, thanks!