Lenovo IdeaPad 320-15IAP MB: dg424/dg524 nm-b301 rev 1.0 Brak obrazu

Witam,

Płyta po zalaniu w okolicach PU701,
Wymieniony ukłąd LV5075A, KBC(IT8986E-BXA)
Bios programowany kilkoma różnymi wsadami, KBC z wgranym oryginalnym wsadem oraz dla testów innym wsadem z forum.
Płyta po uruchomieniu pobiera 0.2A. Po dłuższym przytrzymaniu przycisku power, pobór spada do 1,7A i wraca po sekundzie do 0.2A
Bateria jest ładowana.
Brakuje +CPU_CORE




Proszę o pomoc w dalszej diagnozie

blady313 ha scritto:Płyta po uruchomieniu pobiera 0.2A. Po dłuższym przytrzymaniu przycisku power, pobór spada do 1,7A i wraca po sekundzie do 0.2A

Hello!
Does the machine turn on automatically after connecting power supply to the board (without pressing to the power button)?

yes, turn on automatically.

When I press and hold power button, consumption decrease to 0.17A and come back to 0.2A after second.

The communication between KBC and PCH part of the APU hybrid is missing.
Unfortunately it is damaged APU hybrid almost for sure.

and KBC? it can be damage KBC?

blady313 ha scritto:and KBC? it can be damage KBC?

Yes, possible, but it is quite unlikely in this particular case.

matic ha scritto:Yes, possible, but it is quite unlikely in this particular case.

I belive you, but can you explain me why? I'm trying to understand that.
Signal enable comes from KBC so why you thinkg that APU is damaged?

The KBC chip communicate with the PCH via LPC bus.
In your case it seems this communication is missing.

The issue is probably related to one of the following:
- Bad (corrupted) BIOS chip.
- Bad (or corrupted firmware) in the KBC chip.
- Bad PCH chip.
- Bad resistors or broken trace on one pin of LPC bus.

Given that you had a spilled PCH power supply controller chip PU701, it is bad PCH part of the APU hybrid in my experience.
Other possible reasons in such case are very rare in my experience.