If your Mac is frozen and unresponsive, a forced restart should help. To do this, press and hold the power button until the Mac screen turns off, and then turn on the computer as usual.
Attention! With this shutdown, unsaved data in applications will most likely be lost.
2. Removing removable media
Eject (⏏) or F12
During a crash of a Mac with an optical drive and a disc inside, the system may fail to boot from it and freeze. Press the ⏏ (Eject) or F12 key on your keyboard, or press and hold the mouse or trackpad button to eject the media.
3. Selecting a boot disk
If your Mac has multiple disks installed and the system cannot boot from the default disk, you can open the bootable disks selection dialog and select the desired media manually. To do this, press and hold the ⌥ (Option) key immediately after turning on the computer.
4. Boot from CD or DVD
Likewise, you can instruct your Mac to boot from disk from the built-in or external optical drive. In this case, press and hold the C key on the keyboard.
5. Download from server
⌥N (Option + N)
Once you have a NetBoot server on your local computer that has a bootable system image, you can try to start the Mac using it. To do this, press and hold the ⌥N (Option + N) key combination.
This boot method does not work on computers with an Apple T2 processor.
6. Run in Target Disk Mode
If your Mac doesn't want to start up, you can put it in Target Disk Mode and copy important files by connecting it to another computer using a FireWire, Thunderbolt, or USB-C cable. To start in this mode, press and hold the T key when turning on.
7. Run in verbose mode
⌘V (Command + V)
By default, macOS does not display a detailed startup log, showing only a loading bar. If problems arise, you can enable a verbose log to help you understand at what stage of the download the error occurs. To do this, when turned on, press the shortcut ⌘V (Command + V).
8. Start in Safe Mode
When your Mac won't boot normally, it's worth trying to launch Safe Mode. It checks the disk and turns on only the basic components of the system, which allows you to determine which named programs or services are causing errors. Press and hold the ⇧ (Shift) key to boot to Safe Mode.
9. Single user mode
⌘S (Command + S)
This mode starts the system in an even more stripped down version - only the command line is available in it. Nevertheless, with its help, specialists will be able to diagnose and correct errors if any. To start in single-user mode, press the keyboard shortcut ⌘S (Command + S).
10. Run diagnostics
macOS has built-in hardware diagnostic software to help diagnose hardware problems. Press and hold D to start diagnostics.
11. Run network diagnostics
⌥D (Option + D)
If the boot disk is damaged, then the diagnostic test will not work. In such cases, network diagnostics can help, allowing you to run the test over the Internet. To do this, press the combination ⌥D (Option + D)
12. Recovery mode
⌘R (Command + R)
When booted in recovery mode, you can access Disk Utility, reinstall macOS, and restore data from a created backup. Press and hold ⌘R (Command + R) to enter recovery mode.
If you have a firmware password set on your Mac, you will need to enter it.
13. Network Recovery Mode
⌥⌘R (Option + Command + R)
A mode similar to the previous one, which, in the presence of the Internet, allows you to reinstall macOS by downloading the system distribution kit directly from Apple servers. To use it, press ⌥⌘R (Option + Command + R).
14. Reset NVRAM or PRAM
⌥⌘PR (Option + Command + P + R)
If you have problems with the display, speakers, cooling fans, or other Mac components, you can try to resolve them by resetting NVRAM or PRAM. To do this, press and hold the ⌥⌘PR keys (Option + Command + P + R) at startup.
If you have a firmware password set on your Mac, this method will not work.
15. Reset SMC
A more drastic reset is to revert to the default System Management Controller (SMC) settings. It is applied if the previous method did not help. Resetting the SMC is performed differently depending on the Mac model.
On stationary computers shut down your Mac, unplug the power cord, and wait 15 seconds. Then reconnect the cable, wait five seconds and press the power button to turn it on.
On laptops with a removable battery you must turn off your Mac, remove the battery, and then press and hold the power button for five seconds. After that, you need to install the battery and press the button to turn it on.
On laptops with a non-removable battery shut down your Mac and hold down Shift + Command + Option with the power button for ten seconds. After that, release all keys and press the power button to turn on.
On a MacBook Pro with Touch ID, the sensor button is also the power button.
Check the battery... Sometimes it happens that, due to any external reasons or careless handling, the Mac stopped turning on. Do not sound the alarm ahead of time. First of all, you need to check the following components. If you have a laptop, check the battery charge. Some MacBook models have a battery indicator that is located on the case or on the battery itself. It looks as shown in the figure. It may well be that his battery ran out overnight.
Check the power supply... Try connecting a different adapter to your MacBook. Despite the different shape of the MagSafe connector, MacBook Pro power supplies are interchangeable. If there is no second power supply unit, check the operation of the outlet by connecting, for example, a lamp to it. If it's a desktop iMac or Mac Pro, try replacing the network cable. You can read more about troubleshooting MagSafe power supplies.
Check connecting cables... You may have inadvertently snagged the cable and it does not fit snugly in the socket. Unplug it and then plug it back in.
Check monitor operation... If you're using Apple Cinema Display with a MacBook, iMac, or Mac Pro, check to see if it's connected to a network. If the monitor indicator light blinks in a special way, this may indicate a malfunction. For more information on troubleshooting with built-in or external displays, see.
Check if the components are connected correctly... If you replaced memory modules or hard drive, check that these components are connected correctly. If necessary, disable them and try the installation again. If that doesn't help, return the original parts.
Gray screen... If you turn on your computer and you see a gray screen with the Apple logo and a boot indicator and nothing happens for a long time, try shutting down your Mac, disconnecting all peripherals (printers, external hard drives, optical drives, modems, etc.), Ethernet cables, and turning on the computer. again. If that doesn't help, reboot into Safe Mode. If this does not solve the problem, reset the PRAM and NVRAM.
Flashing question mark... This message indicates that your Mac cannot see the boot volume. This can be caused by a jammed mouse or trackpad button during boot, damaged system files, or a hard drive failure. If the button is actually pinched, release it and try downloading again. If that doesn't work, then check if your Mac sees available boot volumes. To do this, hold down the Option key during boot. If a list of available volumes appears on the screen and there is a Macintosh HD among them, then most likely everything is in order with the disk, but Mac OS X itself is damaged. Renaming or moving the Applications, automount, Library, System, Users folders or mach_kernel.
You can use these instructions to restore it. In general, if you suspect a hardware problem, you can test your Mac's components using the Apple Hardware Functional Test utility. If you have a Mac that came with OS X Lion, you need an internet connection. If your Mac is with earlier versions of Mac OS X, then use a bootable disk or USB flash drive for this. This program is launched by holding down the D key during boot.
Kernel panic... The most difficult error to diagnose. Most often, third-party software can be the cause. However, it is possible that your system is "knocked down" by some piece of hardware, the drivers of which do not properly interact with the Mac OS X kernel. First, try disabling all peripherals and restarting the computer. If the problem persists, try updating the software installed on your Mac. Pay special attention to non-Apple apps. If you are unable to resolve the issue on your own, use Apple's suggestions for resolving the issue.
Apple has developed a powerful knowledge base so that the vast majority of issues can be resolved by users themselves, without the help of a service center.
How I lost my main working tool during the trip.
About a month ago I went to Moscow for a couple of weeks to visit my relatives. And this should not have affected all areas of my activity, because they are tied only to high-quality access to the network and my beloved MacBook Pro 13 ''... There could be problems with the Internet, but the laptop has not let me down on any trip. I didn't even bother about him, and in vain.
On the second day in the capital, I was left without my main means of production.
My advice is to beware of summer beaches and shield Mac from soft drinks.
Can you guess what happened to him? The guys from MacPlus, who were advised by a local colleague, took this laptop for diagnostics, and at the same time shared information about the 5 most “popular” Mac defects. Further, based on our conversation, I will tell you what problems summer can bring with it (and not only).
1. Malfunction of the cooling system
Overheating is often feared, but what exactly happens with your laptop:
Despite the fact that the cooling system of any MacBook significantly outperforms most competitive PC solutions, it still needs to be cleaned at least once a year. Otherwise, it gradually becomes clogged with dirt and dust, due to which its performance significantly decreases over time.
The result will not be long in coming - serious overheating and failure of the motherboard elements is inevitable.
Now you can often hear that preventive work - cleaning the cooling system and replacing thermal paste - you need to perform a minimum once a year.
Of course, this indicator is actually individual and depends on where and how long you have been working on your Mac... If, for example, a laptop has been turned off for 5-7 months (although this is difficult to imagine), the dust in it, most likely, will be much less than in the same, but actively used one.
The fact is that the dust gets into the cooling system through its own "fault". The fan, while drawing hot air out of the case, at the same time sucks in dust from the environment.
Once again, we note that the indicators are individual - they depend on the working conditions, its duration and on the laptop model too. For example, a 15 ”MacBook Pro will get dusty much faster than the same MacBook Air.
It is worth mentioning separately about as thermal paste. Some of its types can freely withstand up to 140 degrees, while others have rather low threshold values at which they cannot cope with the load. In this case, all the required amount of heat is not diverted to the cooling system, some remains “on the microcircuits”. This increases the load, the temperature goes beyond safe limits, the resource in this mode is developed much faster.
In some cases, the dust itself not only contributes to heating, but can also become a conductor of current (of course, this does not happen often, but it is still real).
Thermal paste is also not so simple: it does not always dry out in a year. It all depends on what you do: permanent work in Final Cut or a game of Call of duty will significantly speed up the process, and gentle use, on the contrary, will postpone the problem.
But you shouldn't deviate from the rule: at least once a year you need to show your Mac to a specialist. If it is clean, they will tell you about it directly. If cleaning is needed, at first the laptop will simply turn off during operation or slow down, but you definitely should not wait until it refuses to turn on even after cooling down.
You can remove the cover and look at the state of the device in a few minutes, but repairing devices that have already failed is much more difficult. And more expensive.
2. Troubles with charging or power supply
It's not that simple, there are several options.
The battery "died"
There are two equal options here. Either the battery has worn out and is not suitable for further use, or for some reason it was simply blocked by charge controller... Of course, this won't turn on the MacBook.
There are many publications on this issue. We'll just reiterate the obvious: Mac batteries are very durable, but not permanent, and sooner or later they have to be replaced.
Practice shows that it always happens unexpectedly. Of course, various utilities can now monitor the state of the battery, and the system itself does this. But there is always a possibility that the battery will fail for no apparent reason: long-standing and forgotten contact with moisture, unnoticed overheating or voltage drop, “fault” of a poor-quality charger.
In some cases, a failed attempt to charge the Mac may be recognized by the battery controller as physical problem. In this case, part of the circuit is specially disabled - this is a protective mechanism. The battery cells themselves may be fine, but the battery controller considers it "dead" or dangerous for the MacBook.
By and large, in such cases repair is possible, but it implies transferring the board with the controller from the donor battery to the repaired one and their "coordination" using the programmer. This is not possible for all battery models, but in cases where it is realistic, the repair process is comparable in cost to replacing the entire battery. And the latter, of course, is much more reliable.
There are problems with the power connector
In a particularly hardcore mode of laptop operation MagSafe can fail for several reasons - the connector contacts are oxidized, covered with dirt or worn out. As a result, the MacBook battery is discharged to zero and the laptop does not turn on without recharging.
It's not uncommon to have a faulty MagSafe. It can occur in almost any model, but most often it happens with Unibody models from 2008-2012. Now these Macs are no longer available, but they are used quite actively. Taking into account the age of even the "freshest" copy of 2012, during maintenance work, you have to clean not only the cooling system, but also the surface of the connectors.
The MagSafe connector is always open, and on the contact pad dust settles... It somewhat worsens the quality of the electrical connection, and from frequent connections, the leads are worn out. For loss of contact, tenths of a millimeter is often sufficient.
With frequent loss of contact, the MagSafe board begins to heat up, the battery may fail (the system perceives this as frequent connection / disconnection of the charger), and then the motherboard itself.
So you need to use, of course, high-quality PSUs. And keep the Mac itself clean.
"Covered" power supply
Another reason for the inability to charge the MacBook is a non-working power supply that could fail for a number of different reasons: from the same voltage drops to banal wear and tear.
At the same time, a "working" Mac may well recognize such a block. Charging performance degrades over time. They are quite enough for the system to “see” the power supply unit and show the status “battery is charging”, but a switched off and completely dead laptop cannot be charged with such a unit.
The situation is the same as when charging MacBook Pro 15 ″ block from Air... The process is going on, but much more slowly, and if the battery has completely sat down or "went into protection", a current of sufficient power is needed.
The block must be selected carefully. It's not only the quality of the performance (the original or the factory copy has very good protection against various emergency situations), but also in accordance with the parameters - the power and current of the PSU must meet the requirements of the laptop.
You can use a more powerful charger - it is safe, but a weak one (as mentioned above) is not recommended. In most cases, the Mac will simply charge slowly (for example, if it is turned off and is not consuming power on its own).
If you are working on a laptop connected to such a low-power unit, then the system thinks that it is charging, although in fact it is discharging, because the battery receives less from the power supply during charging than it consumes, and the indication on the battery icon will not tell you about it. The result is battery wear and failure.
3. Serious voltage drop
Burned elements of the motherboard
The worst thing that can happen during a voltage drop is the failure of the motherboard elements. It involves a complete replacement or expensive MacBook repairs.
Such cases are always the most difficult. The whole chain or just one single element "burns out". And the result is known - Mac does not show signs of life. With devices that have survived a voltage drop, you need to be especially careful - problems can be ambiguous, they do not appear immediately.
For example, you have a completely serviceable Mac but discrete graphics don't work or turn on Wi-Fi, although both the module and the antennas are in good order.
The answer is not always on the surface, but recovery is as real as, for example, when replacing a hard drive or other basic repairs. As a rule, such problems do not affect the durability of devices. And if they managed to be eliminated, further Mac will work without problem.
Most often, "watch chains" suffer - this is the name of the sections that are always energized, albeit small. There are also "power" elements operating under high currents in the risk zone.
The battery is "covered"
Due to the large voltage drop, the MacBook battery usually goes into a protection state, but it can also "die" completely. This has already been discussed above.
Power supply unit "died"
A voltage drop very often causes the "death" of a power supply, which fails in whole or in part.
It is safer to replace such a block, because if he saved Mac- it's worth it.
4. Large and continuous load
Burnt out chipset or video chip
MacBook can cope with a very large and prolonged load, but only with a working cooling system, which is regularly cleaned. Otherwise, he will overheat greatly, which will become the cause of his “death”.
More precisely, not only the chips themselves can fail, but also the "strapping" - auxiliary elements that distribute power to the microcircuits.
A video chip (also known as a graphics processor) is the main element, the "heart" of a video card. In modern Mac this chip is on the motherboard.
The chipset is also part of the motherboard, and in some models it also includes a GPU. Plus, the microcircuit performs many other important functions. But even if all the chips "survived", the problem can still appear.
Overheating may break contact Bga- the leads of the crystal itself and the pads on the chip substrate (a mirror square and a square made of textolite with elements soldered onto it).
Even more often and even in the overwhelming majority of cases, the crystal lattice itself fails. The temperature changes its structure and the chip must be replaced. In this case, the problem can be temporarily solved by the thermal shrinkage of the chip, which allows partially restoring the structure of the crystal lattice or returning the crystal-substrate contact.
But, as a rule, when the graphics fail, the chip needs to be replaced with a new one, and the technique itself serves more for diagnostic purposes.
The chip almost always fails during overloads, especially long-term ones. There are many options here: you can "burn" the Mac in an addicting gameplay, leave it overnight to edit a video or render a large project.
A clean cooling system will help here, but it is also not omnipotent. Especially difficult Mac cope with congestion in Windows, at least previous versions (maybe also because there are much more demanding games for this operating system than for OS X).
5. The device was filled with liquid
Keyboard refused
The keyboard is the first thing that suffers when it hits MacBook liquids. At the same time, it can fail completely or partially. If the power button fails, the laptop simply won't turn on. Interestingly, this may not happen immediately, but long after the incident.
Therefore, it is cheaper and more reliable to strictly follow the rule: Filled up the MacBook - go to the service center, even if everything is fine, especially since the diagnostics can be done for free in any case.
The keyboard is one of the most vulnerable places in Mac... It is easiest to fill it. It often dries up and works, but even then it is at risk and may one day suddenly fail.
The fact is that the keyboard itself has a flexible transparent substrate, on which the tracks for each key are laid. It is they who are oxidized. Technically, the keyboard can be repaired, but considering the labor costs, such work will cost almost like replacing with a new one.
Often the keyboard backlight “saves” everything else - a small amount of moisture, penetrating through the keyboard, is delayed by the backlight (it is glued to the keyboard quite tightly and is supplied with a thick film on the back). This is exactly what happened with my Mac.
Short circuit on the motherboard
If liquid gets on the motherboard, a short circuit may occur on it immediately or after a while. All the fault is the oxidation of contacts.
Approximately 40-50% of the devices that are used for repair are flooded or have been flooded at some time. Once again, let's pay attention to what has already become a well-known fact: contact with moisture will not pass without leaving a trace for almost any device, it does not matter, Mac it, iPad or iPhone.
Oxidation almost always happens very quickly, especially if you do not physically disconnect the battery from the motherboard. It is simply necessary to do this, but most owners of modern technology hardly have a screwdriver with their beloved Pentalobe, which is now used in almost all new Mac.
Just turning off the laptop is not enough, while power is still supplied to the board, and the liquid that gets on it acts as an electrolyte. It turns out a homemade battery - the electrolysis reaction starts, its products appear on conductive elements and tracks, and especially small components can be completely destroyed in the process.
Therefore, if you have a suspicion, or you know for sure that water got inside - MacBook repair should not be postponed. At least you need to check the condition. Again, it's better to play it safe, and contact as soon as possible when the damage is still small, because the further - the more difficult it is to bring the Mac back to life.
Sometimes you have to restore the tracks themselves. Particularly difficult is the moisture under the microcircuits. They are not attached to the board hermetically, and the microscopic gap is enough for water to get there.
Cleaning in an ultrasonic bath in industrial alcohol solves two problems at once - moisture leaves hard-to-reach places (water is heavier than pure alcohol), and ultrasound allows you to remove oxides from the surface.
It is also worth noting here that water itself is not so dangerous for electronics, but from experience, almost everything that gets into Mac- aggressive media - soda, coffee, sweet tea, alcohol, and so on. If the board is disconnected from the battery and the block, electrolysis proceeds much more slowly, but in practice the battery is almost always connected.
And we will repeat again. Even if immediately after the incident with your computer everything is in order (at first glance), the equipment is still worth inspecting, because the problem may appear much later, when you have already forgotten about what happened. And, as practice shows, it is much more difficult (and generally not always possible) to restore such laptops.
All's well that ends well - that's for sure
As it turned out, without my knowledge MacBook Pro flooded with something like "Mojito" summer on the beach almost a year ago. The liquid was hastily wiped off the case, but it got inside. In the end, the keyboard contacts oxidized, and the power button did not work corny. The keyboard was completely replaced and the laptop came to life. It's good that the cocktail didn't make it to the motherboard.
While I was drinking coffee and talking with MacPlus specialists, they managed to check the laptop for other problems that were not identified. I got off with a little blood.
How has your Mac ever let you down?
P.S .: for whom everything is bad, we suggest replacing the battery ( 3.00 out of 5, rated: 3 )
None of us will doubt the reliability of Apple's MacBook, because even the 2008 models still compete well with some modern laptops. Therefore, it is safe to say that the Apple Macbook works without freezes and practically does not break, however, this does not mean that in some cases the laptop will work like a clock. Variants of answers why the MacBook does not turn on, and I would like to reflect the ways of their solutions in this article for our readers.
Firstly, a signal that the Macbook is not loading may be the appearance on the computer screen of an icon in the form of a gray folder with a question mark. But for now, there should be no reason for panic, since the reliability of the technology allows you to save your data before the computer is turned off. If we assume that a system failure did not occur, then, in spite of everything, all the information was necessarily saved in the internal memory of the device.
How do I reset my Macbook Pro and Macbook Air?
If your MacBook has a slight freeze and you want to quickly recover all data without loss, then you need to reset the EFI memory settings. To do this, turn off the computer, and then, while holding down the Command P R Option buttons, launch the power key, while continuing to hold all the keys until the next time the system welcome screen appears on the computer screen. This maneuver will help to avoid system freezes and save the data stored on the computer, as well as completely restore work on the Macbook. In the future, it is better to create a backup of your computer data in the cloud storage in case of an unforeseen failure.
If, after the operation, your MacBook Air does not boot up on its own again, check the condition of the hard drive, as well as the moment when the HDD is connected to the motherboard.
Rescuing data when the MacBook freezes is one of the main tasks, so you need to know the order of actions, after completing which, your computer will again be restored along with all the data. But first you need to find out why such a freeze happened? First, there could be a problem with the computer, namely: memory failure, processor error, controller failure, and other reasons. Secondly, a breakdown can occur with the operating system, for example, when it is upgraded to EI Capitan. Thirdly, the reason for the freeze may be the emergence of new connections that are not always compatible with the computer. In the latter case, you just need to disconnect all additional device connections from the USB ports.
To correctly establish the cause of the failure, you need to check the battery and make sure that it is not discharged or stopped working, because if the battery is discharged during the OS program update on the MacBook, then the entire system will probably freeze. So, it is worth considering several ways to fix the freeze problem on your computer.
Method 1. Safe Boot - Safe Boot Mode
First of all, use a security mode in which the MacBook will only download verified content when it starts up. To do this, deactivate the MacBook in order to turn it on in the mode of holding down the SHIFT button. Such a launch of a MacBook takes a lot of time, however, there is no need to rush, because it is more important to complete the download with the least possible loss.
If you have to carry out a more detailed download with a complete clarification of the cause of the failure, then you need to boot the MacBook by holding several buttons: Command + Shift + V. This will allow you to start Safe Mode on your Macbook and view the details of how Verbose Mode started, including the causes of the problems.
What does verbose mode mean? Loading Verbose Mode is a method of loading the operating system, in which specific information about the loaded files of drivers, programs appears on the display and all processes occurring in the system during the MacBook boot process are displayed in detail.
If, after the above boot, your computer can fully recover, then perform a standard reboot of the operating system. If this method did not help you solve the problem of the Macbook freezing, then in the future we recommend that you turn to the next solution to the problem.
Method 2. Download via Disk Utility
It is clear that the MacBook may not turn on and freeze for various reasons. If we assume that this is not a problem with the hardware, but the hard drive is to blame for everything, then it will not be difficult to check the cause if you run Disk Utility or Disk Utility on your MAC.
First you need to turn off your computer. If your MacBook displays a blue, gray or other color screen with a spinning boot button, then, unfortunately, you will have to turn off your MAC forcibly by holding down the computer start button for 5-8 seconds.
Next, to activate Disk Utility, you need to open the recovery mode in your operating system. This can be done in the following way. Hold down two buttons simultaneously Command and R and launch the power key. Upon successful login, you will be presented with a screen named MAC OS X Utilities. Now look for the Disk Utility icon on the open screen to activate it. Next, click the name of your MAC hard drive, which is on the screen to the left of Disk Utility. Next, start the verification by activating the Verify Disk line and wait for it to complete. Finally, activate the verification process by clicking on the Repair Disk line. Then it remains to start your computer again.
Method 3. Start external drive
Sometimes it’s better to play it safe to find yourself in a situation where there is not a single backup copy of your data, and your computer freezes inappropriately. Even if you have repeatedly backed up your data, how do you get to it now? This problem is easily solved by your Apple Macbook, since you can use a special mode of the external disk - Target Disk Mode.
The sequence of actions for starting the external disk consists of the following order. To get started, you need an additional MAC computer for a short while. When the second computer is found, connect them using a certified Thunderbolt cable. The next step is to turn off your MacBook, and if necessary, hold down the Power button for a few seconds until the laptop can boot. After your computer starts to boot, immediately press the "T" key and hold it down until the Thunderbolt icon appears on your frozen color screen.
This starts Target Disk Mode. Essentially, a laptop plays the role of an external drive, not a computer you are used to. If everything went well, then soon the display in Finder will show the external device - the new hard drive. Taking advantage of this unusual convenience, you can copy and save all your necessary data before the computer is restored.
After everything is saved to the external hard drive, you will have to move it to the Finder, as you would with a real drive. Then unplug the Thunderbolt cable and start the laptop by holding the Power button again.
Method 4. Restarting the operating system
When none of the methods gave positive results, and your MAC is still "hanging", the last method remains - reinstalling OS X. To do everything according to the rules, you need to turn on the laptop in recovery mode and exactly repeat all the steps specified in the option 2. In particular, launch the MacBook with the R + Command buttons held down.
After the operating system starts, find the line Reinstall OS X and, following the instructions that appear on the display, follow all the steps to restart the operating system.
If, after all the work done, your MAC does not start again, then, alas, the problem may be in the hardware and you need to contact the service center, since some parts are out of order, or the loop is broken. However, such a failure could also occur due to the replacement of the old one and the connection of new equipment that is not compatible with your OS X. For example, if you put someone else's memory module on your MAC. Therefore, repair your devices only in certified service centers and do not be fooled by cheapness..
Let's take a look at the reasons why your MacBook won't boot after updating your Mac OS system in this article. There are clearly software errors that could have happened due to the fault of Apple itself, or incorrect actions on your part (settings and the update process).
In some cases, the matter can be complicated by the failure of internal modules due to overheating. In such cases, it is better to contact the service center in your city.
This article applies to all MacBook Pro and Air models released in different years. There may be some differences in architecture or description of the Mac OS version.
Reasons why MacBook won't boot after update
The device can behave in a similar way due to a number of different errors. Let's take a look at them:
- Installing updates for the Mac OS operating system (or the laptop installed it on its own, if the auto-update option is activated).
- When you restart (turn on) your device, a black screen was displayed instead of the download bar.
- Looking at this black screen, you heard 3 long beep-beep-beep sounds repeated every 5 seconds.
The official Apple website has symptoms and a description of this error. Three consecutive signals, which are repeated with a five-second pause, indicate that the RAM could not pass the data integrity check.
It turns out that the problem is related to the RAM of the device. Judging by user reports, most often this error is given by the following devices: MacBook Pro a1278, a1260, MacBook Air a1466. Let's consider ways to solve the problem.
Resetting SMC Parameters
If the MacBook does not turn on and beeps, then this is a signal of an error with RAM, which can be resolved by resetting the SMC (System Management Controller) settings. Follow one of the algorithms, depending on the type of device used.
MacBook with non-removable battery
MacBook with removable battery
Such devices are rare, but still consider the algorithm of actions:
Mac Pro, Mac mini, iMac
In this situation, it is even easier to reset the parameters of the system control controller:
- We turn on the device. If it doesn't respond, turn it off by pressing and holding the power button for 10 seconds.
- We take out the power cord from the outlet or device.
- We wait 15 seconds.
- Reconnect the power cord.
- We wait another 5 seconds, after which we turn on the Mac in the usual way by pressing the power button.
Rearranging RAM
This method is suitable for those Mac devices where the RAM can be replaced, and it is not soldered on the motherboard, as is now done on most models. The algorithm of actions is as follows:
To fix the problem where your MacBook won't boot after an update, you can use Boot in Safe Mode. Thus, you can identify various software errors in the system. In this mode, the kernel of the system is loaded with important functions.
When the device is booted into safe mode, the file system is checked for errors, and they are eliminated whenever possible. Therefore, booting your Mac into Safe Mode and then performing a graceful soft restart may resolve the issue.
To boot your Mac in Safe Mode, press and hold the Shift key on your keyboard when you turn on your computer until you see the boot progress bar. In Safe Mode, the boot time of macOS takes significantly longer than the standard boot of the system.
Your Mac may not boot due to a problem with the hard drive. The easiest way to check your hard drive is to use Disk Utility.
First, turn off the device. To start Disk Utility, you need to go to OS X recovery mode. When you turn on the device, hold down the Command + R keys.
If all is well, you will be taken to the MAC OS X Utilities screen like the screenshot below. There you need to click on "Disk Utility", then click on the name of the built-in hard drive, which is located on the left side of the screen and start the verification process by selecting Verify Disk on the bottom right of the screen. We are waiting for the verification to complete.
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If any faults are found, you will be prompted to correct them. To confirm your intentions, click on "Repair Disk". Then restart the MacBook again.
External disk mode
We launch the external disk mode to access information on the MacBook.
