"3 beeps on start up"に関する回答The past couple times my Mac book air battery went down to 0% I charged it back up to 100. Both times, after it hit 100, would then turn off with a dark screen with the 3 beeps. I have only used my laptop several times since I got it 2 years ago. I found this thread last night, what a help!! What worked for me was shift-control-option and power at the same time. Also what worked was command-option P and R and power all at the same time. I don’t know enough what caused this but I think I have a battery issue. Thank you for the fixes I don’t know what I would have done!! Let me add after reading the above, the 3 beeps occurred right before I installed an update. I think that’s what happened last 3 beep episode. I have a feeling it won’t be long before the 3 beeps becomes more consistent. I don’t know for sure, but I’ll just enjoy the fix for now.