Symptoms of MacBook not turning on
When you press the Power button or Touch ID button on your Mac, if you don’t see any images, video, or visuals of any sort on your display, if you don’t hear a startup chime, and if you don’t hear any fan or spinning drive noise, then most likely your MacBook is not turning on. In other words, your Mac has no sign of power at all.
If your MacBook Air or MacBook Pro won’t turn on after a liquid spill, see our article Spilled water on a MacBook Air or MacBook Pro, what to do now?
If your MacBook won’t start up properly, you only see a question mark folder flashing in the centre of your MacBook screen, see our article How to fix the Mac Question Mark Folder issues
If your computer only works with the adapter plugged in, you have a MacBook not charging issue. Check out our article 12 Ways to fix MacBook battery not charging issue
Why is your MacBook not turning on?
A MacBook consists of the following components: a screen, keyboard, touchpad, battery, SSD drive and a logic board. Any of these components gone wrong could cause your MacBook won’t turn on.
Read also: understanding Laptop power sequence
From the moment you press the power button or Touch ID button, to the MacBook displaying the image on the screen, your MacBook has gone through a series of complicated power-on events. The System Management Controller (SMC) governs the entire MacBook power-on process.
Once the SMC detects that you have pressed the power button, the SMC will co-operate with the Intel chipset to create a series of “mini power supplies” of different voltages (e.g. 5V, 3.3V, 1.2V, 1.8V, etc.) in a precisely defined sequence. These “mini power supplies” will power your Mac’s memory, hard drive, CPU, Wifi, keyboard, trackpad and screen.
If the SMC has not received power, or failed to function, or failed to create the required “mini power supplies”, your MacBook won’t turn on.
For deeper technical details of the MacBook power-on process, see our article How does my MacBook power on?
Fix Mac not turning on problem step-by-step
There are lots of reasons why your Mac won’t turn on. We’ll run through various checks, tips and tactics to get your Mac back to work again. In the last section, we will show you how professionals repair Mac computers in the workshop and the resources and equipment used.
3.1 Check for any faulty external devices
If your Mac detects the accessories attached to it have short circuits or draw an unusual amount of current from the Mac, the SMC will cut short the power-on process. This is a safety measure to protect your Mac. You can easily rule out if any device is the culprit.
Unplug all the accessories attached to your Mac including printer cable, USB hub, external USB hard drive, HDMI cable, and Mini display cable, even your Magsafe or USB-C charger. In other words, you just let your Mac stand alone. It could be one of your peripherals causing your MacBook Pro or MacBook Air not turning on.
Read also:https:How to erase a MacBook and restore to factory settings
Occasionally, this simple step would fix the “Mac doesn’t turn on” problem.
Reset the SMC or T2 chip
The SMC is responsible for receiving your action (press power button) then starts and manages the entire power-on process. You may consider the SMC as a tiny computer running a tiny operating system and the software sometimes could go wrong. If this happens to your MacBook, you need to reset the SMC.
You will NOT lose any data in your hard drive by resetting the SMC.
Follow these steps to reset the SMC on a MacBook with non-removable battery:Press and hold the power button for 10 seconds to ensure your Mac returns to its OFF state.
Connect the MagSafe charger; hold Shift-Control-Option on the left-hand side keyboard and the power button simultaneously for 10 seconds.
Release all the keys.
Press the power button to turn on your Mac. Now you have successfully reset the SMC.
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Apple integrated the SMC chip into the Apple T2 Security chip starting from 2018. Follow these steps to reset a MacBook with a T2 chip:
Press and hold the power button for 10 seconds to ensure your Mac returns to its OFF state.
Press and hold these 3 keys for 7 seconds: Control, Option keys on the left-hand side and Shift key on the right-hand side.
Then press and hold the power button as well. Now keep holding all four keys for another 7 seconds, and then release all four keys at the same time.
Wait a few seconds, and then press the power button to turn on your Mac.
Resetting the SMC on MacBooks with removable-batteries is simple.
Press and hold the power button for 10 seconds to ensure your Mac returns to its OFF state.
Remove the power adaptor and the battery from the MacBook.
Hold the power button key for 5 seconds to discharge any remaining electric energy in the capacitors of the SMC circuit. Alternatively, you can wait for a few minutes until the capacitors discharge naturally.
Re-install the battery back to your MacBook. Now you have successfully reset the SMC.
If SMC reset can’t fix the problem, go on to the next step.
Check for a flat battery
If you haven’t used your MacBook for a long period of time or you have an aged or a swollen battery shown as below, the battery could have been completely discharged, causing your MacBook not to turn on.
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The pre-2012 MacBook models have a battery check button and a battery status indicator on the right-hand side of the case.
Push this button. If you don’t see any light, then you have a flat battery.
You need to make sure your MacBook is receiving power from either the MagSafe or USB-C charger. Check if the power cable is undamaged and securely plugged into your Mac and a working electrical outlet. If you’re not sure about the outlet, test it with a lamp or a mobile phone charger.
Use the correct power adapter for your MacBook model to charge the MacBook for about 5 minutes. If possible, try to use the original power adapter that came with your Mac.
If the flat battery causes your MacBook Air or MacBook Pro not turning on, most Macs will power on automatically if you connect a working charger to it. However, there are some models of MacBooks that require a minimum battery power before the Mac can turn on. So wait for 5 minutes. Let your charger top up the battery above the minimum level.
If you can see a green or orange light on the MagSafe connector, it means both your charger and the SMC in your MacBook are working now. The SMC has successfully communicated with your charger and then turned on the light. You may try another charger if you don’t have a light on the connector.
After 5 minutes, press the power button to see if your MacBook can turn on. If your Mac still won’t turn on, or if you don’t have a light on the MagSafe connector, go on to the next step.
3.4 Perform a power cycle
A MacBook has three major states: Off, Sleep and On. Performing a power cycle means you force the MacBook return to Off state.
In a pre-2013 MacBook Pro, there is a sleep indicator on the front edge of the case as shown below. When the MacBook enters to sleep mode, this sleep indicator light will flash. Apple removed the sleep indicator in the recent models. For these newer machines, if you can’t see anything on the screen, it is difficult to tell what state your MacBook is currently in.
If your MacBook gets stuck in the Sleep state for some reasons, your MacBook will not respond to normal wake-up signals such as opening the lid, pressing the power button or clicking the touchpad. You need to force the MacBook back to Off state by performing a power cycle.
Press and hold the power button for 10 seconds then release the button. Now you have forced the Mac returning to Off state. If you have a spinning hard drive in your Mac, you may hear a squeak as the hard drive power is forcibly cut. If your MacBook has an SSD drive, you won’t hear anything.
Now you know your Mac is in Off state. Press the power button again to see if your Mac can turn on.
If performing a power cycle can’t fix the problem, go on to the next step.
3.5 Check for a faulty screen
When you see nothing on the screen, you may think that your Mac won’t turn on. But that is not always the case! Your Mac may be ON already; only the screen is not working. Therefore, it is vital to double-check any signs of power including sounds and lights to avoid a misdiagnosis.
Check for sounds
Do you hear a startup chime? If you do, your MacBook is already on. Wait for 1 or 2 minutes to check if there is any display on the screen, even a quick flashlight. If you don’t see anything on the screen, your Mac most likely has a screen problem. This is not good news as the screen is one of the most expensive components next to the Apple logic board.
Pick up the MacBook; place the vent holes (between the two screen hinges) near your ear. Do you hear any noise from the fan, mechanical hard drive or super drive? Do you feel any air coming from the vent holes? If you hear the noise or feel the air movement, your Mac is on and your Mac has a logic board problem. Your Mac has already started to turn on but somehow got stuck in somewhere.
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Check for lights
If you don’t see anything on the screen, shine a flashlight through the Apple logo on the back of your screen. If you can see a dim image, press the screen “brightness up” button on the keyboard a few times to increase the screen brightness. If you still get the dim image, you have a screen backlight problem. The screen backlight problem could be caused by a faulty screen or a faulty logic board.
Press the keyboard backlight “brightness up” button a few times, if you can see the keyboard backlight, your Mac is ON already. You may have a screen problem.
Press the Caps Lock key, if you can see the light on, your Mac is running. You may also have a screen problem.
Connect an external monitor to your MacBook via a mini display port, thunderbolt port or HDMI port. If you have a display on the external monitor, you definitely have a faulty screen.
3.6 Check for a faulty RAM
If you hear repeating beeps from the Mac, your Mac could have RAM faults that are causing your Mac to not turn on.
If you hear one beep, repeating every five seconds, it means your Mac can’t detect any RAM. If you recently replaced or upgraded your computer’s RAM, check to see if it was installed properly.