Chosen Solution
Hello everyone, My late 2011 MacBook Pro has come to an end. Even if right now is perfectly working when plugged to the charger. After shutting down, due to a completely discharged battery, I plugged the MagSafe in and try to turn it on. Nothing happened even after resetting PRAM and SMC. I unplugged and plugged the battery back in and it magically turned on, but the battery wouldn’t charge even if the charger was plugged in. Strangely the battery was discharging even with the charger on. Once the battery discharged completely, the system shows a crossed battery symbol. Now battery is not recognized and in order to turn on I have to do the reset SMC procedure. During this procedure the MagSafe charger remains Green without changing to Amber. I also downloaded MacsFan control and the result is that “No fans detected on this computer”. Another strange behaviour, when the MagSafe charger is plugged in and show a bright Green, if I unplug the charger the system shuts down immediately. If instead the charger show a lower green light and I unplug the charger the mac continues to stay on, so I guess the battery is still alive. Is my SMC dead? Is there any way via terminal to detect if it working or not? Shall I try and replace the SMC? I have seen from this similar post: Cooling Fan running constantly/not detected by Fan Control Apps. There someone suggested a PRAM battery replacement, Can this be applied to my late 2011 model? Thanks a lot for spending your time reading this. I hope someone can give me a solution for this problem! Cheers
It sounds like you have a faulty charging circuit from your description and the basic troubleshooting, but unless we plug into your Mac a different known good battery there’s no way to tell, you might simply have a faulty battery that can extend its fault to the logic board when plugged in place. If you had a SMC issue it would probably give troubles even with battery unplugged but if I understand right without battery the Mac runs fine. SMC don’t go bad so often unless there’s water damage and from a technical point of you replacing it without testing makes no sense. There’s no Pram battery in your Pro model.
If PPBUS Voltage is 12.56~ and you have 3.42V on SMC RESET unlikely. If PPBUS voltage is 12.23~ check SMC RESET voltage. You should have 3.4v. If you dont, the SMC may have crap under it or the Reset chip isnt working.
Luca - Yes your SMC logic has issues! You really need to take your logic board out to inspect things. If find this is a bit much for you, then your only option is just replace the logic board your self or bring your system to someone who has the skills and tools to diagnose things at the component level.
