Chosen Solution
Hi, I just replaced my old battery with a new one from here on iFixit. Problem is, the MBP won’t boot up from the new battery, but only when plugged in to the magsafe adapter. When my MBP is plugged in, the battery says it has 81% charge, but won’t charge any further (magsafe light is green), and if I unplug the magsafe, the laptop shuts off. I have tried SMC resets already, but to know avail. I put my previous battery in as well, and it worked just fine (both booting up from only the battery, and battery charging). Anything would help! Thanks!
You probably got a defective battery. Too bad iFixit’s 1 year battery warranty has expired. I would try another new battery.
