Lion - Macbook randomly wakes up from sleep when lid is closed

Question

I have aluminium macbook (not pro). I have recently updated to Lion. So far so good - had some minor issues with printer, sshfs, mac fuse. Managed to resolve almost all of them.

There is one issue though i keep on having which almost destroyed my laptop. In SL when i closed the lid there would be no way laptop would wake up itself from that state (unless i connected keyboard, mouse, screen and used in clam mode).

However now every so often i close the lid and mac goes to sleep and then it just randomly wakes up and stays awake. I didn't realized once and my mac spend few hours in its thick sleeve while running. I came home and I could smell burning plastic - aka. my mac melting itself. Luckily didn't catch fire.

So far i tried following:

• reinstall lion - fully wiped and started from scratch
• pulled battery out and disconnected power supply and pressed power button for 10 sec (resets power management apparently?)

Is anyone else experiencing same behavior?

Answer 1

It is possible to determine what caused the system to wake

• Open Console (/Applications/Utilities/Console)

• Set the search filter to 'wake'

  You're looking for the latest entry that has something like this:

  Wake reason = EC LID0
  

  (In the example above, opening the display clamshell caused the machine to be woken)

Here's a list of wake 'reasons' from OSXDaily

This should shed some light on what is waking the machine, then you can go from there.

Answer 2

Does this only happen with the display closed, or does the same behavior exhibit itself when inducing sleep from the menubar/letting it sleep on its own?

If it only happens when the display is closed, it might be worth having it looked at. The way the laptop determines when the lid is closed is through the use of magnets, and if these become misaligned it might cause the laptop to wake unexpectedly when the lid is closed.

Answer 3

I've had similar issues - my MacBook Pro is doing the same thing. So far I've disabled the "allow bluetooth devices to wake this computer" option in the Bluetooth System Preferences (click on the advanced... button). That hasn't solved it, although it has reduced the frequency.

There is also an option in "Energy Saver", "Wake for network access". I've just switched that off, but it's still waking up.

A bit more digging through the syslog gets me this...

Apr 22 15:45:14 MacBookPro kernel[0] <Debug>: sleep
Apr 22 16:15:06 MacBookPro kernel[0] <Debug>: Wake reason: OHC2
Apr 22 16:15:06 MacBookPro kernel[0] <Debug>: Previous Sleep Cause: 5

There's a slightly contradictory note about the meaning of sleep cause 5, but one person suggests it might be a flat battery. Although my battery isn't flat it does always complain about needing to be serviced. So I wonder if that's anything to do with it.

Edit: during those tests I had my iPhone plugged in, charging. Once I took it off charge the problem stopped, and the Mac slept soundly! Seems a charging phone wakes the laptop.

Answer 4

See the power logs for the last 7 hours:

log show --last 7h --predicate 'subsystem == "powerd"'

Filter on DarkWake to see weird wakings:

log show --last 7h --predicate 'subsystem == "powerd"' | grep "DarkWake"