Chosen Solution
MacBook Pro 15" Unibody (Mid 2012) 2.7 GHz not powering on. There was a spark while charging, saw a burnt component on the Magsaf DC - inboard, I have replaced it, but still it doesn’t power on whether on power or battery. no sign of the Fan spinning or light or harddrive spin. Last three digit of my serial number is XXX-XXX-XXX-V35 Thanks, awaiting a solution ASAP, hoping it isnt the Logic Board.
This sounds like a bad AC adapter. This is very common with 3rd party chargers. Apple MagSafe 1 AC Adapter UPDATE check the output of your adapter, here’s what the reading should be: Pin 1: GND (0 VPin 2: V+ (14.5 / 16.5 / 18.5 / 20 V DC)Pin 3: Charge control pinPin 4: V+ (14.5 / 16.5 / 18.5 / 20 V DC)Pin 5: GND (0 V)
