Read on to learn how to troubleshoot one or more of the following MagSafe adapter symptoms:
- Your power adapter won't charge the computer.
- The LED on the adapter connector doesn't light up when attached to the computer.
- The adapter only charges the computer intermittently.
- The adapter's white insulation separates from the magnetic end of the MagSafe connector.
I'm not experiencing any of these problems and just recently purchased a new adapter (6 months ago) when the wire on my last one got frayed.
I have the same problem, intermittently. I think it has something to do with full-screen mode, which I use intermittently. Have you noticed this happening only when you are in a full-screen app?
I also have a MacBook Pro from 2011, and I know for sure my MagSafe power adapter is fine and not part of the problem.
I have noticed a few things that may be hints at what is happening:
- one time, (all??) while my screen was basking in the glow of sunlight from the side, I saw that the screen pixels were indeed "on", that the back-light of the screen was just off.
- Which led me to the conclusion that my MacBook Pro was indeed waking from sleep, the screen was just not lighting up.
- But that theory was disproved this morning, when when waking from sleep, the screen was black, except for my cursor. My cursor was completely visible on a black background. Huh?? It was like some software was putting up a black modal dialog over the whole screen. Also, the Apple Logo on the back of the laptop screen was fully lit -- meaning the backlight was on. The machine was awake (curson moving on a black background), and the screen was fully back-lit.
- I'm not sure yet how consistent this behavior is... I will take more careful notes each time this problem happens in the future... But, it looks like I have rogue software that is trying to make my machine look like it is sleeping.
To "capture" the culprit I think I could set up a hot-key command that takes a snapshot of all running processes in Activity Monitor. This could show what processes are running when "waking" from sleep. nabbing the culprit?
I use Snapz Pro. That is non-standard software running with control over screen functions. Maybe Snapz Pro has a problem? I doubt it, but maybe, because it has hooks into background tasks with video. Snapz Pro is my only 32-bit process. Could Snapz Pro be the cause? I use Snapz Pro all the time.
The problem seems to be related to Full-Screen mode. Could it be possible that full-screen apps sometimes have problems returning from sleep? I know there are viewControllers responsible for handling events when waking. Could the symptoms of not waking from sleep be caused by bugs in full-screen apps?
I have used an Apple TV remote, but a while back I disabled this on my MacBook Pro so that it didn't conflict with my Apple TV usage (the remote, that is.)
I don't think my sleep waking behavior is/was affected by my remote, but I don't really have any evidence one way or the other.
I would like to report that my machine is waking from sleep normally now. The black screen with visible cursor is a feature of the OS, I believe, not some rogue software, like I mentioned above. That was a dumb idea. My machine is fine now.
Thanks for your ideas.
I had a similar problem. I would put my MacBook Pro to sleep by closing the lid or manually by using the keyboard shortcut (option+command+eject), and at least one out of every ten times I would open the lid, the computer would not wake. I tried a number of possile solutions posted on user groups including resetting the System Management Controller (SMC). I noticed a few people said that the problem may have something to do with how the wireless card interacts with other parts of the computer. That led me to the first solution.
Solution 1: Before putting my computer to sleep, I turned the airport off. Every time I did this and opened the lid to wake my computer up, my Macbook would wake without any problems.
But this solution is a little clunky (Having to turn your airport off every time you put your computer to sleep, then having to turn it back on upon waking). Then a rep at Apple Tech Support had me do the following. Since applying this solution, my Macbook has woken from sleep without any problems.
Solution 2: Shut the computer down. Turn the computer on in Safe Mode by pressing the power button and immediately hold down the shift key until a progress bar appears in the lower middle area of the screen. When prompted, enter your password to log on in Safe Mode. Go to the apple symbol in the upper left hand corner of the screen -> select system preferences -> select energy saver. Then under the settings for "Power Adapter" uncheck the box "Wake for network access." Restart your computer normally and make sure that the box is still unchecked.
It's been almost 24 hours now and the problem has not recurred. If this does solution does not work on your Mac, there are several other possible solutions at this link (http://www.maclife.com/article/howtos/how_fix_mac_won%E2%80%99t_wake). From reports on other message boards, it sounds like a number of problems can cause this issue including problems with hardware. But if your computer's problem is caused by an interface problem with the wireless card, this may be a solution worth trying.
I'm not sure if this will help, but I just noticed having this problem on my new MacBook Pro 13" 2012. It would keep "randomly" sleeping and restarts wouldn't help and it was becoming quite annoying. I performed everything under the sun in terms of troubleshooting and once I was about to give up, I noticed something strange. I purchased this computer to replace my very aging original MacBook (Core Duo, vintage 2006) and realized it only did this strange behavior when I stacked the new MacBook Pro on top of the MacBook. When I moved the Pro into my lap, it would instantly come to life.
Short answer: "Magnets". So you could have a similar problem I did, or have a magnet problem as the MacBooks use magnets to determine if the lid is closed or not. Hope this helps.
Yep. Holy crap. I was doing the same "silly" thing. I had my new Mac Book Pro on top of my old white Mac Book. Moved the computer, restarted, and it works now. HMFS how was I supposed to know that. I even had a Genius Bar appointment scheduled - thanks for helping me avoid an amazing pain in the rear end.