iMac won't sleep

[Chubypig]

I've had this problem for a few months and just kept expecting it to go away, but it hasn't. My iMac will no longer go to sleep. The screen will go black as if it's asleep, but the computer never fully sleeps. Any suggestions as to what could be wrong?

 

[fivetoadsloth]

When you go to apple sleep (note to someone, i tried typing option shift k to make the apple logo but it doesnt work, found that a bit odd, it is macrumors, but im not that big on web design so is there any way to get that working) sorry, ill continue when you go to apple sleep you are saying the screen falls black but the hard drive keep spinning? Does the light start blinking? How about command option eject? same result? try opening system preferences and go to energy saver and set it go to computer to go to sleep after a certain amount of time and check put the hardisk to sleep when possible. Otherwise i dont know. good luck

 

[Chubypig]

If i make it go to sleep, it will, however, even with the sleep preferences set, it won't got to sleep by itself. the screen goes black and the light comes on (but doesn't blink, like normal) and the hard drive never stops.