We have found so many forums with owners of MacBook Pros ( MBP ) suffering from the following issue:
1. The MacBook Pro goes to sleep either by closing the lid or just by virtue of time.
2. Upon trying to wake the MacBook Pro, you get a black screen with or without the spinning beach ball of death.
3. Nothing brings it back to life, so you have to do a hard restart (holding down the power button to turn off).
These forums suggested everything from repairing permissions, to a clean install of the Operating System, to PRAM (Parameter RAM) & SMC (System Management Controller) resets, logic board failures, graphics cards failing that need to be replaced, etc.. We tried turning off Sleep Mode and Safe Sleep, an SMC reset, and when those didn’t help, we figured it was a software issue instead of a hardware one.
One forum suggested that USB devices attached to the MacBook Pro could interfere with the normal sleep mode and affect waking fom sleep. We disconnected our external USB hard drive that we use for Time Machine backups, and the problem went away. Thinking that the drive being connected couldn’t be the real issue, here’s the solution that worked for us:
1. Turn off Time Machine.
2. Throw away all Time Machine backups from the USB external drive, including the sparsebundle file.
3. Re-activate Time Machine.
Problem solved: no black screens with the spinning beach ball due to the machine going to sleep and not being to wake up.