To date, iMac is perhaps the most successful representative of All-in-One computers. However, even the ideal is not without flaws: models released three to five years ago often caused our concern: the complete absence of an image made even knowledgeable engineers think more than once, because there may be several reasons for this iMac behavior.
When working with iMac, a black screen has haunted users for many years and still remains one of the pressing problems of this computer.
It can occur for several reasons., both software and hardware, and below will be the most common problems and how to fix them.
Most common software issue, with which faced by users who upgraded to Mac OS 10.9 Mavericks(the problem most often occurs on this version of the operating system, although the possibility of its occurrence on other updates is not excluded). If this failure still occurred when updating your iMac, the black screen will not allow you to work with the system, since from everything GUI Mac OS will only be able to draw the mouse cursor.
You can fix the problem in two ways: by completely formatting the hard drive and reinstalling the system, or by using safe mode to fix the problem. In the second case, you must restart the computer while holding down the Shift key, after which Mac OS will boot into safe mode. Since the black screen on the iMac does not allow you to see the interface, you will have to carry out further operations blindly.
You will need a username and password for the next steps. If you don't know the username, you can find it out by launching your iMac in console mode (Command + S during bootup) and typing “is /users/” without quotes. The last value in the line that appears will be the username. After that, you should restart the computer with the “halt” command.
First, you should wait for the download (when the corresponding scale is full and disappears), and then press the first letter of the username. It is worth noting that in the case where there are two or more users whose name starts with the same letter, the system will select the first one in alphabetical order. Since the problem is resolved individually for each user, to enter the desired account the first few characters must be typed until the system switches to the desired user (for example, if the accounts “AB123” and “AB456” exist, it is enough to enter AB4 to select the second user, after which the system will switch to the desired account).
Then we confirm the choice with the Enter key - the system will switch to the password entry field. After that, you should enter the password and press Enter again, then the system will enter the account (again, without displaying any graphics). When all the steps are completed, it is enough to restart the computer in standard mode. If the actions were carried out correctly, the screen will work again.
A black screen can also occur during the installation of the operating system.(the installation process will hang before reaching the end and the computer will restart). In this case, it is most likely a hard drive error.
If the iMac does not turn on, a black screen may indicate a failure of individual computer components.Thus, such a malfunction can be associated with both the failure of the graphics adapter or hard drive, and the display module itself. If the computer turns on and you hear operation sounds, or if the screen turns off by itself, there may be a problem with the backlight system. In this case, the problem can be eliminated by restoring the backlight circuit or replacing the matrix, which is significantly more expensive (and there is no need to do this)
On iMac, a black screen can also occur when waking up from sleep, but this is only relevant for older versions of Mac OS and iMac 2010 release. The problem is fixed by updating the operating system or blocking the entrance to sleep mode.
In addition, there are problems with the matrix itself.. In the case of iMac, black and white dots on the screen are common symptoms and are “treated” by cleaning the matrix layers from carbon deposits that occur after a certain amount of time the system has been running.
If none of these cases fits your description, but you still observe onimac black screen when turned on, the cause can be identified during hardware diagnostics.
We have analyzed the most common causes of a black screen on imac. If for some reason it was not possible to cope with the problem on your own, you should contact the service center - any screen malfunction can be fixed by professionals as soon as possible.
In some cases, Mac users may encounter a system crash where a black screen is displayed when the computer tries to wake up from sleep, or the user opens the MacBook lid while the devices are active, as indicated by backlit keys or audible alerts. If this is a problem, don't panic. Most likely, you can handle it on your own with the help of the instructions published below.
In contact with
1. Check screen brightness and power settings
Before you do anything, make sure that the screen brightness is at the maximum level (you can increase the brightness with the F2 key), the Mac is running and connected to a power source (even a laptop, as the battery may be dead). If your Mac is using an external display, make sure it's turned on as well.
2. Turn off and turn on your Mac
Often, turning the computer off and on again will be enough to resolve the black screen issue when waking up from sleep. You can do it like this:
- Press and hold the power button on your Mac until the computer turns off.
- Wait a few seconds and then press and hold the power button until your Mac starts to boot up.
3. Reset SMC, NVRAM
If your Mac repeatedly displays a black screen when waking up from sleep, reset the System Management Controller (SMC) and NVRAM.
Owners of modern MacBook models can do the following:
- Turn off Mac;
- Disconnect the power cable;
- Simultaneously press and hold the combination for 12 seconds ⇧Shift + Control + ⌥Option (Alt) + power button;
- Simultaneously release the keys, connect the power cable and turn on the Mac;
- Restart your Mac and after the beep when you turn on the computer, hold four keys for 20 seconds ⌘Cmd + ⌥Option (Alt) + P + R to reset NVRAM.
In most cases, resetting the SMC and NVRAM will fix display and device power issues.
With the release of OS X Mavericks, we began to often encounter system freezes that we had not encountered before. Once you turn on your Mac, it loads correctly (first it shows , then the “wheel spins” under the apple) and freezes at the stage when the user should be logged in. The screen turns black and it seems to you that the computer simply freezes, or its video card or display does not work. But... If you move your mouse or touch your Mac's touchpad, you see a perfectly normal cursor that moves properly and doesn't look like a fatal error. Typically, our customers experience these symptoms after trying to install any system updates.
A biased study of the error led to the conclusion that neither resetting PRAM / NVRAM, nor resetting SMC, nor reinstalling the operating system (including deleting the System folder from the disk root) lead to the desired result. Everything is quite logical: freezing occurs not when accessing the system, and at the stage of accessing the user, and therefore, you should look for the source of the error outside of OS X. Apple's advice to combat such an ailment in most cases comes down to formatting the system disk, installing a clean copy of the operating system, and restoring from a Time Machine backup . But there is a more effective way, similar in effect to magic.
But first, let's make sure you know your username and password. There should be no questions with the second one, but we usually don’t enter the login by a hundred times a day and we may be wrong about it.
- Do you know? Great, skip this part and go straight to the action algorithm.
- Not? Forgot? by the most in a simple way not having another Mac know your "username" will start the computer in Single user mode:
Perfectly! We have the username, remember the password (if the password is forgotten, we have a publication on how to do it, the second way, turning on the super-user). Let's start restoring the computer:
- Turn on (or restart) the computer Safe mode. To do this, when you turn it on, press and hold down the ⇧Shift key.
- When the “thermometer” of the system loading reaches the end and the system boots up, we wait for the appearance of that very ill-fated “cursor on a black background”.
- Enter the first character of your username and press the Enter/⏎Enter key on your keyboard.
- Enter your user password and press the Enter/⏎Enter key again.
- We are waiting for the end of the system setup and restart the computer in any way you know.
Hooray! Your system has been restored! With a great-o-o-o-o-o time saving... We do not quite understand as it works, but it really works. This is evidenced by the numerous positive reviews on the Apple discussion forum and this fact is confirmed by our own experience. It remains to thank
Many of you have probably heard that Apple's operating system is famous for its reliability and low number of errors and failures that occur during operation. However, Mac OS, unfortunately, is not perfect and one day it may just take it for no reason and not boot.
Without a doubt, this behavior of your Mac can be caused by a number of different errors, which need to be fixed in different ways, however, the author of this article in recent times is increasingly confronted with a situation where MacBook won't boot after next operating system update(Mac OS Sierra in this particular case) and emits three loud squeaks at the same time repeating at regular intervals.
Unfortunately, this can happen to each of us, and contacting a service center is often not enough time and, of course, not cheap. Luckily, there's an easy way to try before you take your Mac anywhere. Judging by the reviews on foreign forums, he helped many people save money on contacting the service, more than once such a "hint" helped the author of this article. About him and will be discussed. So, what to do if your MacBook won't turn on?
Showing an error when booting a Mac
As mentioned above, a computer can behave in a similar way due to a number of different errors (at least 4, judging by the help on the Apple website).
However, in our case, the sequence of actions and the patient's symptoms look like this:
- you installed an update to the Mac OS operating system (or the computer installed it itself if you have auto-update enabled);
- when you turn on (reboot) your MacBook, instead of the expected operating system loading bar, you see only a black (well, slightly gray, the monitor's side backlight still turns on) screen;
- looking at this "light black" screen, you heard three long beep-beep-beep sounds repeating at intervals of 5 seconds.
Having carefully studied the official Apple website, we find the symptoms and description of our error:
"Three consecutive beeps, repeated with a five-second pause: RAM failed data integrity check."
Okay, I see, this is the RAM error of our MacBook. But at least some way of solving the officials somehow forgot to offer. But we found it, and it turned out to be easier than ever. Of course, it’s not a fact that this method will help you 100%, but it’s worth a try, because. many have it works.
By the way, judging by the discussions on foreign forums, the following MacBook models most often give such an error and do not turn on: MacBook Air a1466, MacBook Pro a1278 and a1260. It is from the first that we write this article.
Solving the problem - resetting the SMC
So if your MacBook Air, MacBook Pro, iMac, Mac mini or Mac Pro won't turn on and beeps- This indicates a memory (RAM) related error, which can most often be resolved by resetting the System Management Controller (SMC).
Depending on what device you have, follow one of the algorithms below.
If you have a MacBook with a non-removable battery
And these are most modern models, then the algorithm of actions for you is as follows:
If you have a MacBook with a removable battery
Although these, in my opinion, have not been produced for a long time, but just in case, we act as follows:
If you have an iMac, Mac mini, or Mac Pro
That is, one of Apple's desktop computers, then resetting the system management controller (SMC) is even easier:
Using the method suitable for your Mac, you will most likely see the familiar window Mac downloads OS - this means that the problem is solved.
What does resetting SMC settings affect?
If you are not very well versed in computers or are just encountering such a procedure for the first time, then before doing the steps described above, a quite reasonable question may arise: “Will I lose important data or settings on my MacBook as a result of a reset, because this procedure is somewhat similar to "hard reset" on some gadgets?
We hasten to reassure you - no, you will not lose anything important. If you're really interested, take a look at the list of functions that the System Management Controller (SMC) is responsible for, which we are resetting:
- response to pressing the power button;
- response to opening and closing the display lid on Mac laptops;
- battery resource management;
- temperature control;
- sudden motion sensor;
- ambient light sensor;
- keyboard backlight;
- status indicator control;
- battery status indicators;
- select an external (instead of internal) video source for individual iMac displays.
Alternative option - rearrange the RAM
If the above option didn't help and your MacBook still won't start, then it's worth trying an alternative method. However, it is far from suitable for any Mac computer, but only for those whose RAM can be replaced, and not soldered to the motherboard (as is done in most modern Mac models).
If you have one of these computers, then this option may well help you, you just need to know how to get to the RAM slot. The algorithm of actions is very simple:
That's all. Now you know what you can try to do first of all if your Mac does not start and beeps with a nasty signal. We hope that one of the options above will help you solve this problem and save a significant amount of money on contacting a service center.
Fair, not too high or too low. There should be prices on the Service website. Necessarily! without "asterisks", clear and detailed, where it is technically possible - the most accurate, final.
If spare parts are available, up to 85% percent of complex repairs can be completed in 1-2 days. Modular repairs take much less time. The site indicates the approximate duration of any repair.
Warranty and Liability
A warranty should be given for any repair. Everything is described on the site and in the documents. A guarantee is self-confidence and respect for you. A 3-6 month warranty is good and enough. It is needed to check the quality and hidden defects that cannot be detected immediately. You see honest and realistic terms (not 3 years), you can be sure that you will be helped.
Half the success in Apple repair is the quality and reliability of spare parts, so a good service works directly with suppliers, there are always several reliable channels and a warehouse with proven spare parts for current models so that you do not have to waste extra time.
Free diagnostics
This is very important and has already become a rule of good form for the service center. Diagnosis is the most difficult and important part of the repair, but you should not pay a dime for it, even if you do not repair the device after it.
Service repair and delivery
A good service values your time, so it offers free shipping. And for the same reason, repairs are carried out only in the workshop of the service center: it can be done correctly and according to technology only at a prepared place.
Convenient schedule
If the Service works for you, and not for itself, then it is always open! absolutely. The schedule should be convenient in order to be in time before and after work. Good service works on weekends and holidays. We are waiting for you and working on your devices every day: 9:00 - 21:00
The reputation of professionals consists of several points
Age and experience of the company
Reliable and experienced service is known for a long time.
If a company has been on the market for many years, and it has managed to establish itself as an expert, they turn to it, write about it, recommend it. We know what we are talking about, since 98% of incoming devices in the SC are restored.
We are trusted and passed on complex cases to other service centers.
How many masters in the directions
If you are always waiting for several engineers for each type of equipment, you can be sure:
1. there will be no queue (or it will be minimal) - your device will be taken care of immediately.
2. You give Macbook repair to an expert specifically in the field of Mac repairs. He knows all the secrets of these devices
technical literacy
If you ask a question, the specialist must answer it as accurately as possible.
To give you an idea of what you need.
Will try to solve the problem. In most cases, from the description, you can understand what happened and how to fix the problem.
