Chosen Solution
Hey Everyone, my mid-2012 MBP A1278 refuses to start up with the power button. I can only boot it by opening it up, disconnecting the battery, reconnecting the battery, then reattaching the MagSafe which automatically boots it ( put Catalina on it). Magsafe power adapter seems to work fine, bright orange when charging, bright green when charged. Also, keyboard backlight does not seem to be working. Here’s what I’ve tried so far: hold down button for 10 secTried a different chargerBoot in safe mode (but then what do you do?)Reset SMC (How do you know it reset? … no flicker on charger light)Reset PRAM (got the double chime on startup)Hardware test (held down D, ran the test, nothing)Replaced the battery with a new one, conditioned itKnocked on all 4 corners (read this somewhere, didn’t work)Keyboard pressure Right to Left… (read this somewhere, didn’t work)Reinstalled Catalina from Internet Recovery, still no dice So am I to conclude at this point that the power button has gone bad and so I should replace the whole keyboard with power button? Help! PS. wish there was a soft reset of the SMC … not sure it actually reset… is there a way to know? Update (10/14/2020) PPS. I should mention that, once booted, the computer seems to work fine. Update (10/16/2020) @danj Results of Diagnostic…
Update (10/16/2020) @danj here is the results from coconut…
Update (10/16/2020) @danj battery status
Update (10/16/2020) In addition to the new battery, I also put in 2x8 Gb of RAM = 16 Gb which it seems to be fine with…
Your SMC logic has a latch circuit so when the system hits a failure which it thinks is dangerous it will latch so the system won’t startup. When you disconnect the battery you are clearing the latch not the real problem!
Is it working fine right now? I have the same problem. Mine was working fine till yesterday when I replaced DC IN. Now I gotta disconnect the battery then mbp starts automatically when plugged in.
