Register FAQ / Rules Forum Spy Search Today's Posts Mark Forums Read
Go Back   MacRumors Forums > Apple Hardware > Desktops > iMac

Thread Tools Search this Thread Display Modes
Old Apr 23, 2012, 09:16 AM   #1
macrumors newbie
Join Date: Apr 2012
iMac won't start. Powersupply?


I have a problem with my iMac and I hope you guys can help me.
Its an 24 iMac Mid 2007* 2.8 Ghz Core 2 Extreme (EMC No.: 2134 Model No.: A1225).
The iMac suddenly turned off as if sombody pulled out the powercable. If I press the power button nothing happens as if the machine gets no power at all.
So I opened the iMac and removed all the dirt and dust. I thought it might be the PSU but I cant see any optical defects.
When I pluged in the powercable the first Diagnostic-LED light up shortly and went off again. When i pull the cord and plug it in again nothing happens...
I checked the cable itself and tried another one to be sure its not teh cable.
Can I be sure that it is the PSU (because of the LEDs) or could it be the logicboard either?

Any Experiences?

Thanks for your help. And sorry for my poor english.
cpromotions is offline   0 Reply With Quote
Old Apr 23, 2012, 09:21 AM   #2
macrumors P6
Intell's Avatar
Join Date: Jan 2010
Location: Inside
Because the first LED turns on then off again, I'm going to say that it is the power supply.
Last edited by Intell; Yesterday at 3:16 AM.
Intell is offline   0 Reply With Quote
Old Apr 23, 2012, 10:55 AM   #3
macrumors member
Join Date: Oct 2007
I know this will sound weird.....try unplugging the hard drive.
I had a machine I worked on a while ago it seemed like a dead power supply, I replaced it with a known working one and still no go. As it turned out when the hard drive failed it was causing a direct short. After finding the problem I found others online that have had the same problem. It is worth a shot anyway. If that doesn't work then it sounds like the power supply.
eschw95458 is offline   0 Reply With Quote
Old Apr 26, 2012, 01:57 AM   #4
Thread Starter
macrumors newbie
Join Date: Apr 2012
Thank your for the tip eschw95458. I haven't had time to check the drive an I have one more question before I to that. Was it the HDD and the PSU or only the HDD??
cpromotions is offline   0 Reply With Quote
Old Jan 15, 2013, 03:33 AM   #5
Thread Starter
macrumors newbie
Join Date: Apr 2012

thank you for your answers, and sorry for the very long delay. I never thought it would be that hard to get one of those PSUs in germany. How ever I finally managed to get one.
After I replaced he the old one my iMac started up without any Problems. I had it running for a few hours for doing all the updates with no problems. But after I moved it from my workbench to my home office. It begins to boot and after 20-30 seconds it turns off. I can't turn it on again pressing the power button doesn't have any effect. When I wait a couple of minutes and unplug it from the power network I can start it again, but only for about 20-30 seconds and then the machine turns itself off again.

Does anyone have an idea what this could be? Thanks for your help.
cpromotions is offline   0 Reply With Quote

MacRumors Forums > Apple Hardware > Desktops > iMac

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Similar Threads
thread Thread Starter Forum Replies Last Post
2011 iMac i5 Won't Start robastewart iMac 4 Jan 26, 2014 02:38 PM
[Help] Imac won't start up.. marcusnl Mac Basics and Help 1 Jan 23, 2014 01:20 PM
imac 2007 won't start up thedesignfarm Mac Basics and Help 2 Apr 3, 2013 09:00 PM
iMac won't start up all the way Macmanny9812 iMac 2 Oct 10, 2012 10:25 AM
iMac G5 won't start up SimonBook iMac 4 Sep 25, 2012 06:32 PM

Forum Jump

All times are GMT -5. The time now is 03:02 AM.

Mac Rumors | Mac | iPhone | iPhone Game Reviews | iPhone Apps

Mobile Version | Fixed | Fluid | Fluid HD
Copyright 2002-2013,, LLC