Filed under: Hardware, Troubleshooting, Macbook Pro, MacBook, MacBook Air
MacBook Pro tip: resetting SMC saved my day
Here's a timely tip if the battery on your Intel based Mac laptop seems to be operating at less than optimum performance.
The other day I took my MacBook Pro off the charger and was surprised to see only an hour and 40 minutes of run
time, even though the battery was fully charged and only a few months old. It didn't seem right, and I went immediately on the web to make a Genius appointment at our local Apple Store. Then I did a little digging around Apple support documents and found one that seemed promising.
Was it possible I needed to reset the SMC (System Management Controller)? Well, dutifully following the instructions, I shut down my laptop, removed the power cord and unhooked the battery. I held down the power button for 5 seconds, put the power cord back on, and inserted the battery. Surprise surprise, my computer started up and showed about 4 hours of time left on the battery when I went back off the charger. Better still, it really did hold up for that amount of time, so things were back to normal. I canceled my Genius appointment and spent the day congratulating myself for finding the tip, and getting my battery back in shape.
The SMC is a chip on the motherboard that can lose its way, and in my case it needed a little kick to get itself sorted out. This chip has been the focus of some controversy in the past, and Apple has updated the SMC firmware repeatedly. Anyway, this fix worked for me -- might work for you. Here's the link to the Apple Support Document. There are instructions for the Intel MacBooks, MacBook Pros, and the new MacBook Air. Be there or be square.
The other day I took my MacBook Pro off the charger and was surprised to see only an hour and 40 minutes of run
time, even though the battery was fully charged and only a few months old. It didn't seem right, and I went immediately on the web to make a Genius appointment at our local Apple Store. Then I did a little digging around Apple support documents and found one that seemed promising. Was it possible I needed to reset the SMC (System Management Controller)? Well, dutifully following the instructions, I shut down my laptop, removed the power cord and unhooked the battery. I held down the power button for 5 seconds, put the power cord back on, and inserted the battery. Surprise surprise, my computer started up and showed about 4 hours of time left on the battery when I went back off the charger. Better still, it really did hold up for that amount of time, so things were back to normal. I canceled my Genius appointment and spent the day congratulating myself for finding the tip, and getting my battery back in shape.
The SMC is a chip on the motherboard that can lose its way, and in my case it needed a little kick to get itself sorted out. This chip has been the focus of some controversy in the past, and Apple has updated the SMC firmware repeatedly. Anyway, this fix worked for me -- might work for you. Here's the link to the Apple Support Document. There are instructions for the Intel MacBooks, MacBook Pros, and the new MacBook Air. Be there or be square.
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Reader Comments (Page 1 of 2)
Wesley said 2:08PM on 12-14-2008
Any reason to believe this wouldn't work on a MacBook (Rev.a)? My friend is having a similar problem...
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Chris said 2:22PM on 12-14-2008
I had a similar problem, except that my battery had gone bad and I ended up receiving a replacement from Apple. Mine a 2007 2.2ghz model. Fortunately Apple was very expedient in spending out my new battery; I should note that I did buy AppleCare.
PS The battery health was quite low as well below 40%
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GRiNSER said 7:48PM on 12-14-2008
My 2007 Macbook Pro battery also suddenly dropped to about 40 to 50 % of its capacity. Fortunately I was still in the one year Apple Care and after they changed it I have bought the extended warranty on eBay.
Alex said 2:40PM on 12-14-2008
Thanks for the tip. This worked for me as well. I have a question though. When the adapter is not connected it reads 4:39 remaining. But when it is connected the time 0:26. Is that right?
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Jack said 3:24PM on 12-14-2008
I believe 0:26 mean how long it will take to fully charge the battery.
Will said 2:47PM on 12-14-2008
i believe that 2nd time shown when you are connected to power is to show the amount of time left to fully recharge the battery
Tony said 2:45PM on 12-14-2008
Something to keep in mind: if you're enabled the firmware password, you must disable it before trying to reset the SMC...otherwise you won't be able to. (To disable the firmware password, insert your install DVD, hold down the option key while booting, type your firmware password when prompted, then boot from the DVD. Once the menu bar comes up, you can choose the option to turn off the firmware password.)
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naxalite said 2:45PM on 12-14-2008
I wish I could blog about apples and not know about this.
A SMC reset on my 2001 Imac G4 allowed it to know it had firewire ports again (great for the external HD and the iSight), but its never really helped on my 2007 MBP
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David said 2:56PM on 12-14-2008
um, sorry, but DUH. Everyone knows about the SMC (or PMU-power management utility on PPC models). It's a very obvious solution for most battery problems and can most certainly be found using a simple "broken macbook battery" google search. However, this being said, if you're battery is no longer recognized by the computer, the actual battery usually needs replacement.
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Tony said 3:08PM on 12-14-2008
Actually, no, not everyone knows about the SMC, and no, it's not even CLOSE to an "obvious" solution. Please pull your head out of...well, you know, and realize not everyone is as brilliant and all-knowing as yourself.
Simon Arch said 3:16AM on 12-15-2008
I'd like to know why it is that people like David always seem to crop up whenever someone posts a helpful hint like this. No matter how common the knowledge may be, there's always SOMEone out there who doesn't know it.
David said 9:52AM on 12-15-2008
Whoa Whoa Whoa. All i'm saying is that TUAW 10 years ago actually reported on interesting stories and the staff were apple GURUS. Now, they're just a few nerd journalists who *happen* to have visited the apple website a few more times than the average joe/jane. I mean, i can't be the only one who wants old TUAW back, i don't even come here nearly as much as i used to. they messed up the logo, the phto galleries don't even work on my pro with firefox and the articles lack a clear topic. This isn't a blog. It's a dygin cat waiting to be run over by it's owner Engadget. You know now i'm more lkely to go to engadget and search apple because at least they hit the same stories TUAW does, but hours earlier. This blog became pathetic.
Simon Arch said 11:50AM on 12-15-2008
Ten years ago? Seriously? And so what if the site has changed? What of it? I don't see that as being a serious issue. If I did, I'd find a different site to read.
And how silly is it of you to complain that the site has shifted from a technical to non-technical focus in the comments on a post which gives some technical information?
Michael Rose said 4:44PM on 12-15-2008
We try to acknowledge the presence of both grizzled Mac veterans and newcomers to the platform around here.
FWIW, "10 years ago" is a rather hilarious exaggeration (or possibly just ignorance). TUAW's parent company Weblogs, Inc. was founded in 2004.
Xof said 3:01PM on 12-14-2008
What about resetting the SMC on a MacBook Air?
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Maxintech said 5:47PM on 12-14-2008
1. If the MacBook Air is on, turn it off.
2. Connect the power adaptor to a working power source.
3. On the MacBook Air keyboard, press (left) Shift-Control-Option along with the power button once.
Note: You must use the keys on the left side of the MacBook Air keyboard.
4. Wait 5 seconds and press the power button to start the MacBook Air.
Alex said 3:10PM on 12-14-2008
i had to do this to my macbook (not pro) when my bluetooth wasn't turning back on.
my macbook has been working MUCH better since that.
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papzadsl said 3:39PM on 12-14-2008
I just did it on my late '08 MacBook that was gone weirdo about the battery and, first and foremost, with the sleep mode (i.e. in sleep mode it continued to drain battery, and if I put it in sleep mode when I had only 2-3% of battery left and reopened the lid after an hour or so, it was simply turned off).
It seems I regained the full power of my MacBook :)
BTW, I also performed a PRAM and NVRAM reset (turn it off, then back on, and immediately after press cmd+alt+p+r [akwarkd combo, I know] for at least 5 seconds); therefore, I don't know which action earned my deepest gratitude.
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Joe said 3:54PM on 12-14-2008
I have been using a mac for more than 15 years and didn't know about the SMC until a couple of years back when my powerbook titanium was acting goofy.
I hadn't thought about is since then but now that my macbook pro sometimes doesn't totally go to sleep when i put it in my bag, maybe i should give that and the ol' PRAM trick a shot.
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scott said 10:13PM on 12-14-2008
SMC is actually in the battery.
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