2012 MBP Auto-Sleeps?

[jesterscourt]

I have a MacBook Pro (Retina, Mid 2012)
What seemed to be a one-off has happened more frequently and now occurs around once a week:

Using computer unplugged, will shut off/sleep. If I hit the power button to turn it back on/wake it up it will either:

Flash the low battery/plug-in adapter sign
or
Do nothing

I plug in the adapter and it press the power button, it comes back to life. It always has plenty of battery life left, 25%, 37%, etc. once it comes back up.

I have made sure to do all the updates (still on El Capitan, downloading Sierra as we speak)

I have reset the SMC

Energy saver is set to Automatic Graphics Switching, Computer Sleep @ 1.5 hrs, Display Sleep @ 1 hr, Put hard disks to sleep when possible, Slightly dim the display when on battery bower.

This has happened during various activities, just surfing the web, viewing full-screen video, playing games, using iTunes... has happened on a countertop, a wooden table, and on my lap. No magnets/cases around either.

Coconut Battery says that I am running 76.5% of design capacity, and have had 729 loadcycles

It's a four year old computer, so no AppleCare or anything still on the computer, and I'm just wondering if there are any other things to test before I set up a Genius appointment.

 

[mikes63737]

I'd check if there's any relevant info in Console.app (Applications -> Utilities -> Console).

Also, maybe try clearing NVRAM as well, I normally do both NVRAM and SMC for good measure if I'm having any issues.
https://support.apple.com/en-us/HT204063

 

[jesterscourt]

I'd check if there's any relevant info in Console.app (Applications -> Utilities -> Console).

Also, maybe try clearing NVRAM as well, I normally do both NVRAM and SMC for good measure if I'm having any issues.
https://support.apple.com/en-us/HT204063

After resetting the NVRAM, I just now had a recurrence. I was playing Surgeon Simulator and when trying to go full-screen the screen turned off, and the keyboard was no longer illuminated. The power button didn't respond, once I plugged in the power cable it showed 48 percent battery life. I opened up the console.app, but I have no idea what I'm looking at/for...