iMac won't sleep or wake - and allow me to introduce myself

[heavysound]

Hello my name is Alan and this is my first post. I'm a long time Mac user with many apple products besides my recently problematic iMac. So keeping the intro short and sweet...

Sorry to bombard everyone with my problems straight away but I thought this would be a good place to ask for some help.

2 times yesterday I noticed that my imac would not wake from sleep after I left the room and returned. I also observed that it was not normal "sleep". That is to say that the light was not doing it's glow thing and all the internal fans were running VERY loudly. My only option was to hold the power button and force a shut down.

After restart everything seemed fine so I just left it on and went to sleep.

This morning I awoke to find that once again my iMac would not wake from sleep only this time the fans are not going. Also the light is not doing the slow glow cycle but rather a always "on" yellow light. No amount of mouse movement or keyboard tapping has any effect and once again I am forced to do a hard restart.

This time after restart I noticed also that now I am not able to put this computer to sleep at all. When I choose sleep from the pulldown nothing happens to the screen or the processors at all. When i reach around and push the button on the back I get nothing at all....no dialogue box asking "sleep" or "shutdown"....absolutely NOTHING.

So far I have done the following troubleshooting: Numerous restarts, unplugging ALL USB and firewire periperals, logging out and back in as a guest, tinkering with energy saver etc..., and oh yeah I'm on current system 10.4.10

Nothing seems to help. Anyone have any ideas??

 

[heavysound]

Latest update:
none of my expose' functions work now either.
What is going on and why?

Further update:
Disk utility just spins forever and says "gathering disk information".
I'm starting to get freaked out now.

 

[Egidio]

Try starting from the DVD disks. Insert your OS disk and re-start the Mac. When you hit the power button, hold down the C key. That will force your Mac to start from the DVD. Then run Disk Utility from the DVD and check your computer for any damages to your system.

 

[heavysound]

Try starting from the DVD disks. Insert your OS disk and re-start the Mac. When you hit the power button, hold down the C key. That will force your Mac to start from the DVD. Then run Disk Utility from the DVD and check your computer for any damages to your system.

I just did this and it only found minor errors in catalog b-tree and repaired them. I restarted and it is behaving exactly the same. Sometimes when i restart all the icons in the upper right menu bar are gone except for the spotlight icon, that is to say that there is no wireless strength icon, no volume icon, no time/day, or bluetooth icons etc..

I am still able to connect to the internet but it never shows my airport status.

This is weird.

 

[heavysound]

Update....

With this thread being almost totally dead I started to look elsewhere and found the following info I thought I'd post in case anyone else ever has my problem:

"Not going to sleep as with some other issues, such as video not displaying, fans whirring etc, usually has an issue with power functions for your computer.

Try resetting your iMac with the procedure of SMU (System Management Unit):

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."

So far this has entirely fixed the problem for me. But now of course I am curious as to what caused the problem in the first place. I mean what exactly is an "issue with power functions"?? I am wondering if the AC power supply in this house is fluctuating or surging etc..

 

[Egidio]

I read several Apple support articles after you posted your note above, but those articles never said a word about why this problem happens. Very odd. Thanks for posting the solution.