When you set the screen brightness of your Mac to the lowest level, it looks as if the screen has been turned off even though your Mac is still powered on. Newer MacBooks with USB-C charging ports won’t have an indicator light, however you should see a battery indicator on the display while it’s plugged in. Otherwise, it means that the power cable has issues and should be replaced it with a new one. If your charging cable is working properly, you should see a green or orange light on the MagSafe cable.

If you’re lucky, this will fix the problem and your Mac should turn on successfully after it has been charged with enough power. So the first thing you need to do is connect it to the battery charger and make sure that the charger works properly. One of this problem’s common culprits is that your Mac doesn’t have enough battery power left to turn on.

Otherwise, if it turns on but fails to boot up, then skip to the second section.

If your Mac doesn’t turn on after pressing the power button, then read the first section of this tutorial.

In this tutorial, we will outline the troubleshooting steps that you should take to fix a Mac that doesn’t turn on.

Macbook pro 2015 won t turn on