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Whenever I wake up my mac by opening the lid, approximately 20 seconds later it will put itself to sleep again, even though I'm actively working on it. I'm guessing it's "deep sleep" (hibernation) because the indicator light turns completely off, not just blinking.

Waiting until the sleep process is completed and then pushing the power button will wake the laptop again, and this time it will work fine. So the whole business takes less then a minute, but it's still a little annoying.

What causes this behavior, and how can I fix it? This happens every time I open the lid, but it's a relatively new thing, just happening for the past week or two.

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Possibilities include (listed from the best case to worst case):

  1. Incorrect SMC settings. To fix this: read (your situation is described the Power section)
  2. A battery that's not retaining its charges. To check: read about Battery Cycle Count at

There are other possibilities but let's try these first. Feedback if these doesn't work for you.

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There's also the latch/magnet mechanism that can get munged up in various ways but I agree with your 1 and 2 and a hardware issue should be further down the list. – Richard Dec 7 '11 at 14:11
Trying option (1) seems to have no effect, unless I'm doing it wrong. Is there any way to know whether I have done it correctly or not? Regarding option (2), the laptop is brand new and its battery cycle count is indeed low. – Oak Dec 8 '11 at 0:59
Hi Oak, sorry to hear that. There's no audio or visual feedback that you've done the SMC reset right. Only that your specific problem doesn't reoccur. Since (1) didn't solve the problem, I'm guessing that this is more likely a hardware problem (e.g. battery sensor not working -- I've seen that). Since your MBP is brand new and covered under the 1st year warranty, strongly suggest that you bring it in to the nearest AppleStore or the retailer you bought it from for service. One more thing, strongly recommend that you buy AppleCare which extends your warranty to 3 years from date of purchase. – Global nomad Dec 8 '11 at 15:58
up vote 0 down vote accepted

The problem sorted itself out. How? I don't know. Why did it happen in the first place? I don't know. But if any future victim encounters this question looking for a solution, be aware it might go away by itself after a few restarts.

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Glad to hear it went away. Trust me, nothing is more troublesome than having your Mac fall "sick". – Global nomad Dec 13 '11 at 19:22

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