Ursprünglicher Beitrag von: Dan ,
What I can tell you is your flight didn’t hurt your system as you had it with you in the passenger cabin as carry-on. If you had checked it its possible the baggage hold temp dropped below freezing! Then it gets into the amount of time it takes for the cold to seep into your luggage. As the cold could damage things. So what do we need to focus in on? I’m suspecting your battery is just at the end of its life. What you’ll want to do if you can is setup on a second system a bootable external drive which is setup with [https://coconut-flavour.com/coconutbattery/|CoconutBattery] and I would even setup the user account to automatically run it so it takes less time to load up. As soon as it does get a snapshot of the main window before your system shuts down. As your external drive was the startup the screenshot will be on it so you can salvage it from the other Mac system. To help prove the issue would be to disconnect the battery following [guide|38382] to at least Step 3. Now press the power button with nothing else connected for a good minute. Then plug in your MagSafe charger your system should spontaneously startup and as long as you don’t disconnect the cord your system should stay running. Are you able to get that far?