IMAC A1418 / MB: 820-00430-a / does not turn on, Lights 3 of the 4 LEDs and turns off.

[gabrielA7]

Does not turn on, lights 3 of the 4 LEDs and turns off and stays like this, presses the power and repeats.
I saw that the room LED lights up only when the screen is connected, so quiet.

We have all the power supplies, even processor, 1.8V
One thing I found strange, it has a very low resistance in the Vcore is giving 1 Ohm , work with notes and such, I know that this is normal in some processors but with this resistance only take video card so found it strange.

I suspect that there may be some leak in the processor.
Anyway, when I press the power, it appears voltage Vcore and the processor does not heat up to the point of burning your finger as when it is short, you know...

Anyway, we have memory tension and everything, I have no oxidations.
Could it be something related to BIOS?

[mon2]

Hi.

1) posted in the laptop forum. Should be in the desktop forum.

2) LED 4 will light once the LCD panel is properly detected.

https://www.ifixit.com/Answers/View/...her+board+only