It may be that the problem is with the power cord. If you have a friend who has a Mac power cord that will go with your device, give it a try to see if that solves the problem. If so, finding a used power cord on eBay might be an easy solution (we don't recommend buying third-party power cords that aren't made by Apple, however, as the chances of them being faulty and potentially dangerous are high is larger). If you recently had a power outage, this could be the cause: your power adapter may have been damaged by a power surge and you need a new one If you don't give a sign of life, you can do a reboot, which means forcing your Mac to restart after you turn off the power.
On a MacBook, you need to hold down the power button for ten seconds. Usually, you will hear a squeak when the Mac is forcibly turned off. After ten seconds of waiting and a restart, hopefully, everything will be fine again. If your Mac is a desktop computer, you'll need to unplug it and leave it plugged in for at least ten seconds before plugging it back in and trying to restart it. On M1 Macs, if you hold down the power key, you may see the startup options load - assuming the Mac is working properly. If you can access the startup options by holding down the power button, you can go through these options below to get your Mac up and running. We'll discuss this below. The following also describes how to revive your M1 Mac using a second Mac and the Configurator app. macbook bildschirm reinigen
If restarting your Mac doesn't help, or if pressing the power button on the M1 Mac doesn't open startup options, there are a few other simple things you can try before moving on to the more complicated steps. If you're using a desktop Mac like a Mac Pro or Mac mini, this might apply to you. If you didn't connect a separate monitor, you can skip this step.
You may be having a problem with the monitor that is attached, not the Mac itself. Listen to your Mac to see if it makes noises when it starts up. It is possible that your Mac will turn on but not startup because it cannot access the screen - if so, you are most likely having a hardware problem with the display (rather than a general startup problem).