2012 MBA...Sleep Drained my Battery...Is This Normal?

[JoelBC]

The thread title says it all...

I charged my battery to 100% while working, put the MBA in sleep mode, returned 18 to 20 hours later and my battery was down to +/1- 25% ...

Am curious as to whether this is normal and what can / should be done to avoid this from happening...

Thanks,

Joel

[cedwhatev]

Check to see if Power Nap is checked on while battery is running. Same thing happened to my Mac when I first got it. I did this, along with SMC reset and haven't had a problem since.

[RightMACatU]

I have the same problem... and Power Nap is off.
Everything was fine this summer when I bought my MBA with ML 10.8.0
I too will loose at least 25% overnight (12-14 hours) and this is new since 10.8.1.

[Bigserver1]

I lose 1-2% max overnight. Power Nap is on for me.

This is one of the best features of the MBA in my opinion. My old macbook pro would lose 10% overnight at least when it was brand new, at the end it would lose 25-30% overnight.

[robvas]

Sounds like it's not saving to the hibernation file and keeping everything in RAM?

[JoelBC]

Originally Posted by cedwhatev

Check to see if Power Nap is checked on while battery is running. Same thing happened to my Mac when I first got it. I did this, along with SMC reset and haven't had a problem since.

Appreciate the response...I checked and noted that PowerNap was off...I did an SMC reset and will test the result overnight...

It is now 11:30 PM EDT and I just shut down my MBA (now using my Windows machine)...I will post the battery loss in the morning hoping that it will be minimal...

Originally Posted by RightMACatU

I have the same problem... and Power Nap is off.

Everything was fine this summer when I bought my MBA with ML 10.8.0
I too will loose at least 25% overnight (12-14 hours) and this is new since 10.8.1.

Not a good news story...one would hope that they would have addressed something so basic.

Originally Posted by Bigserver1

I lose 1-2% max overnight. Power Nap is on for me.

This is one of the best features of the MBA in my opinion. My old macbook pro would lose 10% overnight at least when it was brand new, at the end it would lose 25-30% overnight.

I want your results!!!

Originally Posted by robvas

Sounds like it's not saving to the hibernation file and keeping everything in RAM?

Hmmm, new to Mac so do not know but, that said, how does one fix this?

[Jaypi]

Do you have any external harddrives or other external devices plugged in while it's in "sleep mode"?

[JoelBC]

Originally Posted by Jaypi

Do you have any external harddrives or other external devices plugged in while it's in "sleep mode"?

Hmmm, interesting I believe that the night that I noticed the battery drain that I did have a USB drive connected to it...please explain how / why this would be an issue noting that it is no problem with my Windows machine...

TIA,


Joel

[JoelBC]

Update....

I put the MBA into sleep mode with a 95% charge and woke up with it at a 94% charge...lesson learnt, do not leave a USB plugged into the MBA because for some reason it continues to power the USB drive even when in sleep mode...wonder why it does that, anyone have any ideas?

Thanks,


Joel

[Jaypi]

Yes it's useful when you want to charge your iPhone overnight e.g. and you don't have a power adapter.

Btw. I'm happy about every "Vote up"

[JoelBC]

Originally Posted by Jaypi

Yes it's useful when you want to charge your iPhone overnight e.g. and you don't have a power adapter.

Although I understand your point I would think that at the very least they could / would make this an option within the Settings | Energy applet...I for one would like to disable power to USB connected devices when *in sleep mode while on battery power*....

Joel