A friend of mine had a problem with a MacBook Pro, the problem was that it would not turn on, so i took a look at it and here is what i came up with
The battery was completely dead, effectively disabling the SMC (System Management Controller).
Without the SMC, the system will refuse to boot unless you bypass the SMC.
To bypass the SMS and make the computer run, you do the following
1- Disconnect the power cable.
2- Hold down the power button for 10 seconds (or more), then while still holding the power button down, connect the power cable and keep the power button pressed down for another 10 seconds (or more), then once the 20 seconds are over (10 without cable and 10 with cable), release the button and press it again like you normally would to start the computer.
Your fans will run at full speed (resulting in a loud computer), it will be slow, and it might crash or restart itself, in short things will not be working fine, what you need is a new battery.
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Stuff that only applies to my friend, so skip this part
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Here are the specs of my friends laptop.
When you want to look for a battery online, you should be looking for
Macbook Pro A1286 Early 2011 battery (Does not apply to all readers).
I did a search, but knowing that you will be taking it to a service person to install it means that a bad choice on my end (even with a money back guarantee) could mean paying twice to the repair person, so it is not as simple as it seems for me (Since you won't be installing it yourself).
The original battery (OEM) costs $110 it seems, batteries from other providers seem to cost anywhere from $25 to $70, with the $25 batteries having super bad reviews, and the ones for $70 being ok it seems. still, the complications (having to take it to someone to install it) leave me confused. so a safe bet would be the OEM (Original apple battery) but then that's more than double the price
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Once you install the new battery, you will need to reset the SMC, the repair shop will probably do the reset for you, but just in case.
Shut down the computer.
Plug in the power adapter.
On the built-in keyboard, press the Shift, Control, and Option keys on the left side and the power button, all at the same time.
Release all three keys at the same time.
Turn on the computer.
You are done
Hi. I’m having a similar problem. My initial battery was dead and I ordered a new battery, replaced it and it started working. I didn’t do any SMC reset or charged the new battery after installing it. I used the battery until the new battery drained so that I can charge it fresh. But it’s not charging. The MagSafe LED is always on green.
Do you think it could be because I didn’t reset the SMC when I first installed the new battery? Do you think if I install another new battery and do an SMC reset, it will be fine?
I would say No, it will probably not run fine if you get the new battery similar to the old one, i would guess the problem is the new battery, buying the same one again is not what i would do.
you probably can not damage your battery this way, might initially present you with a problem that needs a solution, but if it is not charging even after you reset, i would guess the chip on the battery is bad (from the moment you got it).
NOTE: Lithium batteries are completely different from the old NI-MH batteries, what you did should not affect the battery’s life or usefulness in any way especially if it was drained only once.