1 iMac 21.5" EMC 2428 doesn't turn on, no fans. Only 1st LED.
My iMac doesn't turn on.
On the logic board is only the first 1 Diagnostic LED turned on. No chime, no fans, no hdd. The power Button is okey.
What i find is:
The 4st PIN on power supply output connector shows 12,05V
The 6st PIN on power supply output connector shows 4,95V
The 1st PIN of J600 shows 12,05V
The PIN 2 and PIN 3 shows 0 - 0,2V
PIN 4 of power supply output connector is railed to PIN 2 and 3 of J600 but they doesn't have 12,05V
It is correct? Or should they have also 12,05V?
Is the power supply fail or maybe the cables from power supply to logic board?
Is this a good question?
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Wow! I'm impressed! Not many people can spit out these numbers and schematics this readily.
by Seji the veggie
kamilerdmanski pin 2 and 3 should have 12V as well
by oldturkey03
@Oldturkey03
Also in off or standby-Mode ?
Do yo come from Germany?
Can you write me an email? But I unterstand it right other? Pin 4 of power supply are connected directly to pin 2 and 3 of j600?
by kamilerdmanski
Do I understand it right? PP12V_G3H generated PP12V_S0? Which transistor is responsible for this? Through PP12V_G3H flows 12.05V. What does PM_SLP_S3 have to do with it? Can someone tell me which measurements I have to perform?
Image of PM_SLP_S3 is updated in the Question
by kamilerdmanski
Nobody can help me???
by kamilerdmanski
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