27" iMac suddenly won't turn on… completely dead? (late 2009 2309)
Model: Late 2009 iMac 27" A1312 2309 (Core 2 Duo)
Need some help please! I woke up one morning recently to find my iMac was dead to any input. It was working fine the night before, I didn't shut down and just let it go to sleep on it's own. There is zero response when the power button is pressed, no boot chime, no screen response, no fans/hard drives spin… nothing.
What I've tried so far:
- Different power sockets, different power lead
- Reset SMC
- Replaced PRAM battery
- Replaced iMac power supply
- Removed graphics card
There is only one diagnostic led lit on the logic board (labelled LED601) when the iMac is plugged in:
There are 4 LEDs in total and it's the led furthest from the board edge that lights up. Strangely the service manual for this model seems to list the LEDS in an opposite order to my board:
I assume the LED that is lit up must be LED 1? ( indicating that trickle voltage from the power supply has been detected by the logic board).
Does this mean that it's most likely a logic board fail? why would the logic board suddenly fail overnight when iMac was sleeping?
Ist dies eine gute Frage?
5 Kommentare
I have exactly the same problem; changed the power supply, but nothing.
Where can I find the diagnostic LEDs? So that I could have a check?
J. Willemsen
von Willemsen
The lights are to the right of the RAM slots on the logic board.
von mayer
How long did you hold the power button? Try keeping it depressed for about 1-2 minutes......
von Paul Bowyer
Is there a diff solution? I've tried replacing the power supply, replacing the cables, unplugging for 10 seconds, foolishly taking it to the Apple store, and pulling the ram. I can't seem to figure out what's wrong with this computer.
von joswillia86
So happy I found this post, it worked for me as well. Thank you appreciate it man.
von Kendall FreshdaPrince Bowen