iMac a1418 Led 1 blink


New member
Hello leaders,
Motherboard number: 820-3588

I have a problem with an Imac A1418, she turns on when she wants, I have replaced the original power supply and it does the same.
The led diagnosis:
Led # 1 turns on and when I press the power button it blinks 1 time and led # 1 stays on.

I recorded this video for you:

I have tried turning it on without ram and it does the same.
I replaced the battery on the board and I have the same result.

Any bad resistance?
I really don't know, I'm starting with electronics, a push I need from you wise men.

Last edited:


New member
Thank you, I am going to request that now, it will take me at least 19 days to receive those pieces, should I take into account any other matter?


New member
This is the first suspect...

Greetings leader,
I have already made the change of the Q8450 artifact, it turns out that led number 1 continues to flash.

It turns on when it wants, sometimes I press the power button and it starts normally and everything works perfectly, but most of the time it does not turn on and the effect of the blinking is the one that I have already mentioned Led # 1 and the other 3 LEDs remain off.

Thank you very much, Blessings from the highest ...