I have a fairly new white Macbook, the kind with a built-in, non-user replaceable battery, model MacBook6,1.

The thing's Power Management Unit is clearly on the fritz-- the battery indicator says "no batteries available" (while clearly running off battery power), the magsafe adapter won't light up, and the fan is constantly running at full bore. According to Apple, this calls for resetting the PMU as follows: "On the built-in keyboard, press the (left side) Shift-Control-Option keys and the power button at the same time."

Here's the catch: The left side shift key, the control key, and the left side option key are all dead, due to an unfortunate beer spill some months ago. The other shift key works, but the directions clearly call for holding down the LEFT HAND Shift-Control-Option keys, all of which are dead.

Are there any other ways to reset the PMU, or am I SOL?


If you feel confident enough the only other way I know is to take the MacBook apart, remove the battery, hold down the power button for 5+ seconds and then put it all back together again. Sounds simple but it could get messy if you haven't taken one apart before.

If you do take it apart you could use this time to try and fix the the keyboard and give the poor thing a clean inside...

  • It worked! Thanks a lot! The tri-wing screws were a little tough, but it was totally worth it and easier than I thought it would be. ifixit.com/Guide/Repair/… – Zach May 3 '11 at 0:53
  • Also, I feel a bit like an idiot now. There was no need to remove the tri-wing screws and take out the battery. I could have just taken the bottom case off (easy) and disconnected the battery connector cable (also easy). Oh well, the more you know! – Zach May 3 '11 at 11:48
  • I'm glad it worked for you, I see the question got transferred from Stack Overflow so I didn't see your reply! – David May 3 '11 at 20:05

I know the article says to use the built-in keyboard, but it may be worth trying an external wired keyboard plugged in via usb.

  • I'll try that next! – Zach May 3 '11 at 0:52

I've been all over the web today looking at this very problem. One thing that WILL NOT WORK is an external USB keyboard. It must be the built in keyboard. When you hold down those three keys you are completing a circuit inside the Macbook. The only other way I've found during my research is removal of the battery then holding down the power button for a while.

  • You might have some luck taking the bottom case off the laptop, and then disconnecting the battery cord, and then holding down the power key. You shouldn't need to take the battery out completely, but it's still a little risky. – Zach Oct 5 '14 at 3:00

you click Input language on the right top area and then click show keyboard viewer. Then you can press the keyboard by using your mouse.

  • -1 You can't show the keyboard viewer if your laptop is turned off. And to reset SMC/PMU you have to shut down your MacBook (Pro/Air) – klanomath Oct 8 '15 at 10:18

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .