Replaced Battery, System will not turn on.
I replaced the battery in my friends MacBook Pro Retina 2012 using the part and guide here on iFixit. After double checking my work I reinstalled the bottom plate, plugged in the mag safe charger (light was green then amber) and turned it on. I then turned my head to pull up the battery calibration procedure (maybe 30 seconds) and when I looked back the MacBook was off.
I pushed the power button, nothing.
I reset the SMC, the MacSafe charger flips from Green to Amber, but system will not power on.
I disassembled, rechecking for any loose wires, tripple checking the magsafe connector. Also ran a continuity check with my multimeter through the magsafe pcb through the connector pins (fine).
I tried unplugging the battery and starting with just the magsafe connector. No change.
I reassembled and let charge for ~12 hours. No Change.
I’m not sure what else to try. I don’t want to declare it dead as I am getting some feedback from SMC resets, but I’ve run out of ideas.
given that the system initially started, is it possible that the iFixit battery killed my system board?
Thanks for any help or idea’s you can give me.