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MacBook not turning on after battery replacement and battery not charging. I replaced the battery as should then the following happened: 1 - first the MacBook was turning on but battery was not charging and display was not “turning on”, only keyboard and it’s functionalities as backlight controller and etc. 2 - then I removed and placed the battery again and now it’s not turning on anymore, the MacBook looks like is rebooting over and over. Here is a video of the behavior: https://youtu.be/adJTWhdvaQ0
First off do a SMC Reset. If that doesn’t work, I’d try unplugging the optical and hard drives to see if they are preventing the laptop from coming on.
Are you sure its connected to a good outlet? Do you have a second MagSafe charger? Within the Vid it appears the LED on the MagSafe connector is not lighting up. Also double check the connections review this: Apple Portables: Troubleshooting MagSafe adapters Your Battery test with the blinking single LED is telling me the battery is fully discharged which is why your system is not starting up as the systems SMC services won’t let you. Once you get the MagSafe connector to light up (Amber during charging) and then once the battery is charged it will go to a steady Green. Your battery checker will slowly inch up so all of the LED’s are lit as the battery charges (8 LED’s if I remember correctly). If your MagSafe doesn’t light up or is a faint Amber or Green you may have a deeper problem.
