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So I left my macbook for about a week at my workshop. Battery is totally empty. When I plug in the magsafe adapter, it stays green (not charging). The white light on the front flashes in time with what sounds like the hard drive just starting to boot then failing. Battery indicator flashes to show its empty. I tried reinstalling the battery, no luck… I replaced the battery just two months ago with a green cell. Please forum gods, help me!
You need to make sure you are using the correct wattage adapter for the MacBook. My 2012 MBP needs the 60W adapter. If you are using an undersized adapter (45W), it won’t provide enough PEAK power to start up the MacBook. Consider leaving the charger connected for a while to see if the battery comes back up because as long as there’s charge in the battery, the MacBook can use both battery and power adapter to start up. Remember the PEAK power is used when first starting the MacBook as everything turns on and updates the system that it’s working.
