Chosen Solution
My Mac tends to run hot even though I clean it for dust and keep it on a hard, flat surface when in use. On day it just “clicks” from inside the body and the screen turns black with the noise of power leaving the computer. It won’t turn back on and when I plug in the charger, it vaguely flashes Amber/Green. After a couple of days of rest, I tried plugging it back in (mac turned off) and it starts charging for a couple of minutes and then stops and back to flashing orange/green. I have tried disconnecting the battery and connecting it again, but no luck. Update (07/10/2019) I did decide to go for a new logic board, BUT just to make sure before I purchased one, I plugged in the charger yesterday and “magic sound” my MBP 2012 starts charging and turns on. I run diagnostics, checks heat and fan and battery and everything gets the OK. So I decide to calibrate the new battery, so I let it charge all the way up plus a couple of hours extra, and then drains the battery for power and leaves it with no charge overnight. Then this morning it’s back to square one - MagSafe charger flashing orange and no life. What the f… is wrong with this machine?!:-D Update (07/11/2019) I did decide to go for a new logic board, BUT just to make sure before I purchased one, I plugged in the charger yesterday and “magic sound” my MBP 2012 starts charging and turns on. I run diagnostics, checks heat and fan and battery and everything gets the OK. So I decide to calibrate the new battery, so I let it charge all the way up plus a couple of hours extra, and then drains the battery for power and leaves it with no charge overnight. Then this morning it’s back to square one - MagSafe charger flashing orange and no life. What is up with that?
The oscillating MagSafe LED is telling you the battery is gone. Given the systems age that would not surprise me. Here’s the needed part MacBook Pro 13" Unibody (Mid 2009-Mid 2012) Battery and here’s the guide you’ll need to follow MacBook Pro 13" Unibody Mid 2012 Battery Replacement Update (07/11/2019) To be clear: You put the 2009 battery into the 2012 system and visa-versa. ● The 2009 battery didn’t change your 2012 system symptoms ● The 2012 battery is running the 2009 and has 612 cycles. If that’s so we do need to look deeper. Was the 2012 battery discharged fully? When you plugged it in to the 2009 when you checked it. Lets clean the MagSafe connector faces and make sure the pins in the charger are working correctly. Review these Apple T/N Apple Portables: Troubleshooting MagSafe adapters and Find the right power adapter and cable for your Mac notebook make sure your using the correct charger as well.
