My Macbook Pro(mid 2014 15') keeps shutting down unexpectately, usually acompanied by very loud fan noise. This problem has pestered me for quite a while. I don't remember exactly when it started, but I am sure it happened before I upgraded to the latest Catalina OS. But now it reaches a frequency that render the Mac unworkable. I tried to reboot it in safe mode, but the same thing happened in safe mode as well, though seems less frequent. I tried to reinstall the Catalina through recoverary mode but it can not be done because it shut down while downloading the files. Although the Windows bootcamp works fine. Is there any suggestion about what could be the problem and what I should do to fix it? If there is any supporting documents I can provide, please leave it at the comment and I will find it for you. Thanks in advance.
The first thing you want to do is to backup your data. This issue may worsen and being unable to access/lose important data is the worst thing that can happen.
I recommend the following procedure:
- Try to save the files with target disk mode and/or recovery mode (I would do both a copy of the raw data with target disk mode and a time machine backup). You could also try to take out the HDD and connect it to another Computer if this step fails.
- If you can measure the MacBooks temperature try to check if its an overheating issue.
- Reset NVRAM/PRAM and do a Hardware Test. Your Mac might be able to identify the issue by that.
- If possible, try to start from another Mac startup disk and check whether its a general macOS issue or the specific version installed
- As safe mode seems to work better it might be some software. Check the activity monitor to identify unused/unnecessary software and quit as most programs as possible. You might be able to find some (background) task that is using much Energy/CPU/RAM (used Energy basically translates to heat). Also have a look at startup items. A very drastic solution is to take out the battery and run the MacBook only with the battery chord plugged in. This will throttle the components a lot.
You can find the mentioned startup modes here: Startup Options
Other than that, you should try to find a local repair store/Apple Store.
I hope this is any help. Good luck!