Mid-2012 Wake from Sleep Problem

[bunnspecial]

I have a mid-2012(non-Retina) 15" Macbook Pro that I have been having a strange problem with the last few days.

I'm running 10.9.5 as the primary OS(although I have El Capitan installed on a secondary partition).

In any case, when I'm finished with it in the evening I generally put it to sleep just by closing the lid. The computer stays plugged in all night.

When I access it the next morning, it will seemingly wake from a "deep sleep" as if the battery had run down. I will get a grayed out screen along with a progress bar showing the "wake" process. I bought the computer used, but it had the battery replaced under Applecare right before I bought it(i.e. it showed 1 cycle the first time I started it). It's currently at 37 cycles, and gets what I'd consider "healthy" charge/discharge cycles(i.e. down to 40-50% at some point most days, and an occasional discharge down to 10-20%).

This seems to only happen overnight when plugged in. The computer goes to work with me every day, but usually is put away and unplugged-it's sometimes 8-9 hours before I access it again, and it will wake right up as normal.

Similarly, I don't have a problem with the computer plugged in or unplugged when it's put to sleep for a few minutes or a few hours.

Any ideas about what could be going on?

 

[jdelgado]

I had a similar problem with the same computer (mid-2012 non-retina) . After to what you describe, I had problems charging it. The charger light was amber, but the computer did not acknowledge it was charging; to it was green although the computer showed it needed to be charged. After that, it sometimes reported 0% charge, although I knew it had charge.
Took it to Apple a few days ago. It was diagnosed with a faulty motherboard and had some charging pins burned.
I suggest you take it to the shop and have it diagnosed.

 

[bunnspecial]

Thanks-fortunately it's under Applecare until January, so I'll take it in and have it looked at.