My MacBook Air mid 2009 worked for 3 months without any problems on Yosemite.
Two days ago the built in mouse stopped working along with the built-in keyboard. Right after it woke up from sleep mode but the light is still on. After pressing the Power button, it asks me to shut it down, so the system did not crash.
At boot I'm able to clear the SMC and VFR (?) RAM. Both did not work. After I reboot, the machine won't respond to mouse or keyboard input. Also a USB mouse and keyboard won't work.
I always had to hard reboot the MacBook (holding power) After some time, it wouldn't boot (black screen). After leaving it off for ~5 mins, it would boot again, but I was faced with the same error. After some research, and the problems at startup, I think it might be an EFI specified problem. Reinstalling has only worked for half an day, then after wake up it wasn't responding.
The problem might be caused after the OS X 10.10.2 update. In the update log I couldn't find any EFI-specified updates (EFI and SMC is also up-to-date).
Anyone able to reproduce this error? I can't get it to work again (without reinstalling it).