Welcome to the MacNN Forums.

If this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed. To start viewing messages, select the forum that you want to visit from the selection below.

You are here: MacNN Forums > Hardware - Troubleshooting and Discussion > Mac Desktops > Imac G5 will not boot after power outage

Imac G5 will not boot after power outage
Thread Tools
Chester
Fresh-Faced Recruit
Join Date: Jan 2013
Status: Offline
Reply With Quote
Jan 28, 2013, 07:19 AM
 
Imac G5 20 inch isight ...
this happened before and I found help from some one who posted a method of removing all connections to the Mac ... including the power chord ... then ... something like hold in the start button for some time ... replacing the connections and pressing the start button ... It worked but I forgot the sequence.
Any one with the answer?

Thanks
     
chris v
Addicted to MacNN
Join Date: Jan 2001
Location: The Sar Chasm
Status: Offline
Reply With Quote
Jan 28, 2013, 10:41 AM
 
That's probably the pram reset instructions for an Intel iMac --

From Here:

Reset your computer's PRAM (parameter RAM) by doing the following:
If you iMac is on, turn it off by pressing the power button until the computer turns off. You should hear the fans stop working.
Press the power button to restart your computer and immediately hold down the Command, Option, P, and R keys simultaneously. Make sure to keep holding down all four keys while the computer starts up.
When you hear the startup sound for the second time, let go of the keys. If you don't hear a second startup sound, repeat these three steps again; the second startup sound indicates that you have successfully reset the computer's PRAM.

If it continues to give you problems, you should open it up and have a look at the capacitors -- they went bad on lots of these. Google for "iMac bad capacitor" and you'll find plenty of info on how to identify them.

When a true genius appears in the world you may know him by this sign, that the dunces are all in confederacy against him. -- Jonathan Swift.
     
P
Moderator
Join Date: Apr 2000
Location: Gothenburg, Sweden
Status: Offline
Reply With Quote
Jan 28, 2013, 06:22 PM
 
No, I think he's describing the SMU reset procedure. That seems like the right thing to do if the iMac won't boot. If so, this is how.
The new Mac Pro has up to 30 MB of cache inside the processor itself. That's more than the HD in my first Mac. Somehow I'm still running out of space.
     
Chester  (op)
Fresh-Faced Recruit
Join Date: Jan 2013
Status: Offline
Reply With Quote
Jan 28, 2013, 08:52 PM
 
With multiple attempts, after peripherals were unplugged,... I plugged in while depressing the start button, ... released it ... pressed it again and ... that wonderful C chord! Backup completed and now to the store for a new battery fur the UPS that I will use this time.

Thank you P for the link :

"try resetting the SMU. To reset the SMU on one of these iMacs:
Turn off the computer by choosing Shut Down from the Apple menu, or by holding the power button until the computer turns off.
Unplug all cables from the computer, including the power cord.
Wait 10 seconds.
Plug in the power cord while simultaneously pressing and holding the power button on the back of the computer.
Let go of the power button.
Press the power button once more to start up your iMac."
     
chris v
Addicted to MacNN
Join Date: Jan 2001
Location: The Sar Chasm
Status: Offline
Reply With Quote
Jan 29, 2013, 05:12 PM
 
I stand corrected! Glad it worked.

When a true genius appears in the world you may know him by this sign, that the dunces are all in confederacy against him. -- Jonathan Swift.
     
   
Thread Tools
 
Forum Links
Forum Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts
BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Top
Privacy Policy
All times are GMT -4. The time now is 11:59 AM.
All contents of these forums © 1995-2017 MacNN. All rights reserved.
Branding + Design: www.gesamtbild.com
vBulletin v.3.8.8 © 2000-2017, Jelsoft Enterprises Ltd.,