MacBook Pro not going to sleep

[millerrh]

For some reason over the last couple of days I've noticed that my MBP doesn't go to sleep. It was sitting idle all last night and never went to sleep, just turned the display off (in closed lid mode). My system prefs are that it should fall asleep in 20 minutes.

 

[coledog]

My MBP had that same sort of problem. Try restarting it.
What ended up working for me was an Archive and Install of OSX.

 

[chris.niziolek]

Anytime you close the cover, it should go to sleep. This is because when the cover is closed airflow is restricted. I have a couple of suggestions to try and fix this. One, Restart your computer. I hope that you have done that already. Second, Zap the PRAM. (Hold Down ":Apple: + Option + P + R" on restart). This usually takes care of some simple problems. Third, Contact your apple store and hopefully you have Applecare and can get it fixed for free.

 

[millerrh]

My MBP had that same sort of problem. Try restarting it.
What ended up working for me was an Archive and Install of OSX.

Already tried restarting it a couple of times. If I use the buttons on the side of my cinema display I can get it to fall asleep.

So what exactly is an Archive and Install? Is that an option when you put the OSX disc in? I understand about reinstalling OSX, but what is the "archive" part of that?

 

[coledog]

Archive and Install keeps all of your settings and Applications etc. It just reinstalls the system files.

 

[millerrh]

Tried resetting PRAM and also did the Archive and Install option and reinstalled OSX and it still won't go to sleep.

I wonder what could be going on...it just seemed to stop working for no reason. No new hardware or software installed or anything. I thought maybe the last security update might have caused it, but reinstalling OSX didn't fix it, so I've got no idea.

 

[millerrh]

UPDATE: This only seems to be happening when I am using my external display/keyboard/mouse setup. I am using my laptop now and set my power settings to:

screen off: 1 min
sleep: 2 min

And it is going to sleep! Interestingly enough, it is going to sleep 3 minutes after my screen turns off, so it's still not obeying what the power management settings are telling it to do, but at least it is sleeping.

Could this be something with my hardware/USB hub causing it to not sleep? It will sleep if I to go -> sleep, just not on it's own like it is supposed to. I have not changed any hardware and this problem came up out of nowhere, so I'm not sure why it is happening.