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ghporter · May 29, 2010, 01:58 PM

My 2007 Aluminum iMac doesn't go to sleep on its own. I can select Sleep from the Apple menu and that works, but it does not go to sleep when the Energy Saver preferences settings say it should.

I don't have anything odd running-especially nothing new that I've added recently-that might keep the machine awake. I recently installed VirtualBox, but it does not appear to be active at all. I don't see anything suspicious in Activity Monitor, either, just (at the moment) Firefox, Activity Monitor, and background things like Window Manager and kernel task...

I have reset the SMC per Apple's instructions (shut down, unplug, hold power for 5 seconds, then plug back in and restart), without any change in behavior.

brassplayersrock² · May 29, 2010, 02:23 PM

Are you using anything bluetooth by chance?
A mouse, keyboard, phone?

I was getting these exact symptoms on my old powerbook when I was using a non-apple bluetooth keyboard and mouse combo.

It had something to do with the keyboard and mouse looking for the computer every few seconds to “talk" with it.

ghporter · May 29, 2010, 02:30 PM

I have a Magic Mouse. It's sitting on the desk when I leave the computer to let it go to sleep, and it is not moving. I've had the MM for quite a while, and never saw this behavior before. The Magic Mouse goes to sleep with the machine-or at least it does when I actively put it to sleep.

I'm running 10.6.3, by the way, and have updated everything that's been pushed to Software Update up through today.

ghporter · May 29, 2010, 04:42 PM

Well I experimented. I turned off my Magic Mouse and viola! The iMac slept all by itself. I wonder why it suddenly couldn't do that with the mouse on?

brassplayersrock² · May 29, 2010, 09:46 PM

Check the MM battery level using the bluetooth icon in the upper bar. If it’s low, the MM might be struggling to figure out what it needs to do; which in your case, have it go to sleep with the computer.

Try trashing and deleting the .com....bluetooth.plist then restarting if the battery levels are reasonable.

Good luck.

edit:

Did a little digging in the bluetooth prefs.

In the advanced settings, there’s a thing to tick that says “allow bluetooth devices to wake up this computer”

That could be it too.

ghporter · May 29, 2010, 10:55 PM

The computer slept normally with the mouse off, but when I turned the mouse back on and tried again, the machine stayed awake, so it's obviously the mouse.

The battery is at 87%, so it shouldn't be worried about what to do. But the Advanced BT pref DID say "allow bluetooth devices to wake up this computer," so I unchecked that. I'll give it another shot and report results.

Thanks for the help!

ghporter · May 29, 2010, 11:33 PM

Well unchecking the "allow to wake" box didn't help...

Big Mac · 09:32 AM

It's been my experience that on some hardware (at least) Mac OS X won't auto sleep on idle activity if there is any application-based network activity occurring. On my G5 from Panther through Leopard, sleep wouldn't occur unless I basically let it sit with only the Finder running and no other applications open. I think my MBP auto sleeps normally, though, which is obviously more important for a laptop to be able to do. Have you tried closing all applications and then seeing if the insomnia persists?

ghporter · May 30, 2010, 08:38 AM

That was the next step. The only thing I typically leave running is Entourage. I've pretty much always been that way, and the computer has slept fine up until recently.

Big Mac · May 30, 2010, 09:32 AM

Yeah, a mail client can definitely cause a Mac compu-insomnia.

ghporter · May 30, 2010, 11:36 AM

But in this case, it did not. I completely closed Entourage, so that nothing was running at all, and the machine still did not sleep on its own.

I really thought it was my Magic Mouse not sleeping because the machine slept normally if I turned the mouse off, but I didn't think to check into any other MM troubleshooting steps. Is there something that I should look at about the mouse? Should I perhaps delete this pairing and make a new one? Also, I have a number of obsolete pairings listed in Bluetooth-I was going to delete them anyway, but I'll do that first and see whether that has an effect before I do anything else.

Finally, what might I look for in Activity Monitor that would point to a background process or some app that doesn't show in the Dock that could be at fault?

Big Mac · May 30, 2010, 04:03 PM

Have you reset the SMU? It controls sleep, so that's the next thing I'd try.

ghporter · May 30, 2010, 06:05 PM

It was the first thing I tried, and I used the steps I listed in my first post.

I've gotten the machine to sleep, though this has taken a lot of work and it's confused me. I had thought that it was either the mouse not sleeping or not properly communicating with the computer, but in later tests even having the mouse off didn't make it sleep. I deleted a couple of log on tasks that looked suspicious (like a Kodak wireless sniffer) but that didn't help. I disabled Wallpaper Clocks; no luck with that. I finally turned OFF both BT and AirPort and the machine slept. One thing at a time, I'll re-enable or turn on what I turned off, and I think that will lead me to the offending system. I'm starting with Bluetooth and the Magic Mouse.

ghporter · May 30, 2010, 07:14 PM

I now have Bluetooth on (including "allow device to wake this computer"), Entourage is running, and the machine sleeps at the time set in Energy Saver. I've just restarted Wallpaper Clocks and we'll see if that has any effect.

I still have AirPort off. This machine is wired into my network so I don't need it, but if it turns out something about wireless networking was keeping the machine from sleeping, I have to wonder what it is and why...

ghporter · May 30, 2010, 09:48 PM

Well so far, it seems that Wallpaper Clocks was the culprit. Since it updates every minute, it sort of makes sense that it could prevent the machine from sleeping. I checked with AirPort off and Wallpaper Clocks running, and it just didn't sleep on its own. I'm leaving AirPort off, as I don' t need it, but I'm confident that it was not involved in the issue.

Now I need to find a new desktop background, but there are much worse problems to worry about.

Big Mac · 07:38 AM

Makes some sense - sounds like bad coding if so. I'm sure I don't have to belabor the point (and hopefully this advice will help others with their computer problems), but when you're troubleshooting issues like these you should close every third party application and utility you can find. With those sorts of issues, always suspect anything third party - especially anything that runs in the background all the time.

ghporter · May 31, 2010, 06:39 AM

I've been troubleshooting for over 30 years, but some things still slip past me-like something that is so "background" that I don't even think about it... Lesson learned. I hope.

On the other hand, I am certain that after I installed Wallpaper Clocks, the machine DID sleep on its own. I have no idea what explicitly changed, but whatever it was, it was probably in a Software Update. Fixing something that didn't work quite right for OS X seems to have slightly broken this third party app, just enough that it didn't let the machine sleep at certain points.

mrtew · Jun 5, 2010, 09:52 AM

We have three Macs... two iMacs and one MacBookPro that all have completely different purchase dates and software and instal histories on them and are used by different people and none of them sleep. I think most everyone thinks that because their display is sleeping and there isn't a sleep light on them anymore that the computer is asleep even thought it's not. If you can hear people logging on and off iChat it's not asleep folks. I just always use my sleep button and don't worry too much about it but would like to know if there is some way to get them to sleep like they used to.

Big Mac · Jun 6, 2010, 04:37 PM

what Macs don't have sleep lights anymore?

mrtew · Jun 6, 2010, 05:10 PM

The new iMacs don't. I really miss them too.

ghporter · Jun 6, 2010, 05:22 PM

Originally Posted by Big Mac

what Macs don't have sleep lights anymore?

At least since the introduction of the aluminum iMac in 2007. I have one of the earliest ones, and it has no sleep light at all.

driven · Jan 23, 2011, 03:15 PM

I actually came (search) here to see if anyone else had problems with their iMac sleep lights not illuminating. Well, that answers that question. :-)

Veltliner · Jan 31, 2011, 10:14 PM

My 24" white iMac has acquired insomnia.

It used to go to sleep perfectly, and then, since about a year, he's not sleeping on his own, but only with the help of the power button.

Also, when the screen goes to sleep, it sometimes wakes up with a jolt, goes bright without anything happening.

Something in OS X?