just wanted to give an update from earlier. my local MUG (Mac user group) believes that this problem is software not hardware related. However, after my 4th call to Apple Care since Mavericks -- I got moved up to a Senior Tech or Level 2. Once again, I have a 2012 MacBook Air 13.
He claims it is a hardware problem and he wanted me to get my Air looked at by Apple for logic board failure. I hemmed and hawed and disputed this assertation. The tech claims that because the PowerManagement.plist file does not recreate itself when I delete it -- this is indicative of logic board failure.
I even did a clean install of Mavericks via the download from Apple using the Recovery (boot to Command + R) and this .plist file was missing. I trashed the entire SystemConfiguration plist folder and they all recreated themselves except for PowerManagement and AutoWake.
1. PowerManagement did recreate itself when I set the default Computer Sleep to something other than 15 minutes
2. AutoWake recreated itself when i created a sleep event (ex. put this Mac to sleep at 2:15 PM)
I contemplated simply using this Air as a Boot Camp machine in Windows 7. Mavericks handles Boot Camp way better than Mountain Lion in my opinion. However, ultimately, I wanted to give this Senior Advisor at Apple Care his satisfaction and send in the MacBook Air. I chose the mail in over the local Apple Store because the store has a bad habit of taking about 7 days for a Mac repair.
In March of last year I lost this Air for 7 days due to a faulty hard drive. Apple couldn't even get their own proprietary part in a timely manner. Therefore, I am a pretty unhappy customer.
I got through to Apple Executive Resolutions and offered a proposal -- to be able to buy a non-retina MacBook Pro at 1/2 the student price or $500. They responded that they cant do this -- but they can offer $100 off a refurb or $899. Or I can just use my student discount (which I can do anyway) and buy one at $999. At $999, I am a Dell or Lenovo customer. Enough of this garbage!!!