To check your hardware, use the Apple Hardware Test utility on systems manufactured before June and the Apple Diagnostics utility on newer Macs. AHT comes on one of the Mac OS X installation discs that shipped with your computer, or on a flash drive or hidden recovery partition; Apple Diagnostics can be found on your startup drive. Apple Diagnostics uses that connection to run the test if necessary and to provide support recommendations.
Before you run either utility, disconnect external peripherals. If you recently installed new or additional memory in your desktop Mac, you may have inserted a chip incorrectly or the RAM you purchased may be defective. Along with running Apple Hardware Test or Apple Diagnostics, you can remove the new memory chips and reinsert your original RAM to see if that cures the problem, effectively pointing you toward your upgrade as the source of your boot failures. To test RAM chips without using a testing utility, you can insert a known good chip and swap in your new RAM one chip at a time until you find the problematic one.
If you see an onscreen flashing question mark when you try to boot, your Mac can't find a viable operating system installation from which to boot. This can happen if your system forgets the startup disk assignment you set in System Preferences. It also may mean that your OS files have become corrupt or you tried to install an OS version older than the Mac itself.
If the system eventually boots, open the System Preferences from the Apple menu and reassign your startup disk. If the flashing question mark remains, start up from the Mac OS X installation disc that came with your computer or the recovery partition installed on your hard drive.
Elizabeth Mott has been a writer since Mott has extensive experience writing advertising copy for everything from kitchen appliances and financial services to education and tourism. Skip to main content. Power Before you assume you have a computer problem, rule out the possibility of an electrical problem. Hard Drive A hard drive failure prevents your Mac from reading the operating system files it needs to operate. RAM If you recently installed new or additional memory in your desktop Mac, you may have inserted a chip incorrectly or the RAM you purchased may be defective.
Next day when I opened Like after, 8 hours or so It didn't turn on. I tried everything present on this and other forums, apple communities etc.. Finally, in the evening decided to open it up and disconnect the battery. The moment I started to unscrew it, I removed one screw, and just thought of checking once more, before I unscrew all.
I pressed power button and BAM! There were slight hiccups though, while doing resets, at time it was not turning on after reset, but may be after min or so it turned on.
Where is the power button on my iMac? - 9to5Mac
I then restarted and shut down mac several times, and it went all smooth. There was an OS update to Same thing I did yesterday night, closed the lid and today morning when I opened it, It isn't turning on. Please tell me is there anything else I should try. I'm not in a state to goto apple store, as the nearest one is miles away and I have exams to study for and all my notes are in it. Show 5 more comments. Reece reecee. Open, remove and clean the logic board for liquid damage. Likely there will be corrosion on the bottom of the board.
Intermittent issues as you described in the comments of pccheese answer, is usually caused by liquid. This has probably affected some of the soldered components as well. And hey, it has turned on after quite a few hiccups. It behaves like as if, nothing has ever happened. This is whats been happening from past 3 days, I'm going through agony the whole day and late in the evening it starts.
I even shut it down and also restarted it quite a few times and it was fine, just like before, but i gotta feeling tomorrow morning I'm gonna go through the same agony. I too thought of cleaning the logic board, I saw some tutorial on it, and that made me scared. What if mess up something more?
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I have already messed up the bottom outer lid pretty badly, while opening it, had to drill out two screws. Try disconnecting the keyboard from the trackpad, and plugging the charger in this will turn the Macbook on, if you disconnect and reconnect the battery beforehand. Leave it running with the keyboard disconnecting overnight or something, to see if it is fine. What light is the charger when it goes dead? Don't mean to be disrespectful, but I get a lot of my customers claiming it has never been liquid damaged, but I see corrosion on it.
If you live in a humid environment you can get condensation Vs a true drink spill. A wet case from rain or snow can also be the source. Disconnecting the keyboard cable directly from the trackpad is a hassle to do for testing purposes. It's probably better to just unplug the trackpad connector as that as the keyboard cable is plugged into the trackpad connector board. Otherwise if you really want to unplug the keyboard cable the screwed in battery has to be removed to get to it. Hmm could it be corrupted OS in a way?
Anyway try holding alt when you turn on the MacBook it should display a boot menu The one usually with a hard drive icon and a internet recovery icon, the recovery icon sometimes does not pop up or takes time to pop up but anyway one of those icons should appear. Leave it on that screen and see if it shuts off by itself. Show 26 more comments. Sarah Nait sarahh I have been looking up the internet for someone having the same issue as I do, and after a lot of searching, I found you!
I felt like I was alone with this issue. I have the same Macbook as you as well. Local service centers says no issue with power button or anything and unable to help. James Crowley.
1. Check your charger’s cable
Posted: February Took it to a authorised repair centre. I took it home, worked perfectly. The next day, dead again.
They ran diagnostics on it for 24 hours and could find nothing wrong. Kept it in the store a few more days. Will see what happens next… would love to know if anyone found out the cause.
Posted: July It still is doing the same thing. Sometimes it will power on right away, usually right after its shut down or it wont power on at all and could take minutes hours or days before it starts again. This is only happening on Mac book air. Never had a laptop do this before and no liquids have ever been spilled on it.
July 26 by Dan. I charges and holds a charge.