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I’ve replaced my Macbook Pro’s battery (following the guide from iFixit) and the computer did not “recognise” it. MacBook Pro 15" Unibody Early 2011 Battery Novodio replacement for Model No.:A1382 (10,95V - 77,5Wh) It refused to turn on if only on battery power (not plugged). And it did’t charge the new battery. This new battery wasn’t empty (6 Led green of 8). The only way for me to turn the MBP on was to plug in the MagSafe connector (which is always on the green light). Each time I plugged the MagSafe connector, the MBP turn on automatically (without pushing the start button). When the MacBook Pro was on, I checked the Alimentation part in the System Info, and it showed very “normal” info (Manufacturer : TOP , Charge left : 5362 , Charge max : 7260 , Voltage : 12044). I had reset the SMC and the PRAM, no change. So I assumed that it was a problem with the replacement battery and put back the original battery. The original battery works well. I putted back the new battery again. I had the same problems of the first time. Same automatic boot when I plug the MagSafe Connector. Same “System Info”. Please help me.
If the original battery works and the new knock off battery doesn’t, you don’t need to be asking questions. Use your own judgement.