If your Apple MacBook is not turning on there could be multiple levels of issues that can affect its booting process. You just need to find out the prime cause to diagnosis the possible breakdown and for that you can also take help of Apple Technical Support at your desk. Check below the top reasons that can stop your MacBook from turning on or affect booting process.
RAM Related Problems
Insufficient or faulty RAM also creates problem while turning on your MacBook. If your MacBook beeps three times it means there is RAM issue, check either you have low RAM or there is technical fault in the RAM slot which need be checked by accessing chip. If you have two RAM chips, pull out each one by one and watch which one affects its booting process.
Dead Battery or Bad DC Adapter
If your MacBook battery is dead you cannot turn it on, and you can check it by connecting to the power and turn on. If it starts, it confirms the battery is dead and not charging to give power backup. And dead battery could be due to bad DC charger you are using for charging your MacBook. You can use another adapter to check the charging, and if problem persists, it means there is another issue that could be detected only with the help of MacBook Technical Support.
Hard Drive Related Issue
If hard disk of your MacBook got damaged, corrupted or erased you will face booting problem. If your hard drive got damaged you need to replace it with the new one as per compatibility. Corrupted hard drive often gradually start showing booting related issues that can be solved by replacing the hard disk with new one. If despite of replacing hard drive your problem persists, just get the Apple mac support to find the issues and troubleshoot the error with best solution.
Operating System Related Issues
Not turning on your MacBook means there could be operating system related issues. To check that, try booting off an OS CD and run the apple disk utility to repair the disk or you can also try other applications to repair that. If you fail to repair, then reinstall the operating system. But before that get Apple Mac Help to keep the backup of your hard disk and erase all the data.