Hi all. I have a problem with my notebook. Recently I bought a Macbook Pro Mid 2012 (mod A 1278), motherboard mod 820 - 31115b, which had a fault. It did not light but was following a specific sequence. I leave the YouTube link where I have it on video.
The question is that I disassembled it to measure the tensions I had in the multimeter, with the schematic of the board and the board view file in another machine, in order to discover the reason for the failure.
When I measured the voltage that the power jack had, the multimeter showed that in the middle pin (adapter sense), it had 2.3 volts instead of the 3.42 volts it should have, and in the attached pins on both sides it had 18.8 volts.
(IMAGE: power jack A1278.jpg)
Until here everything was fine, until I accidentally made contact with the pencil of the multimeter between adapter sense and one of the pins of the PP18V5_DCIN, to which there was a spark and the notebook did not light up more with the form that I had described them. Now, when measuring again cno the multimeter, the adapter sense throws 0.1 volts and the pins PP18V5_DCIN throw 18.8. volts
(IMAGE: power jack A1278 NOW.jpg)
Could someone give me a hand to guide me ?? From already thank you very much!
When I measured the voltage that the power jack had, the multimeter showed that in the middle pin (adapter sense), it had 2.3 volts instead of the 3.42 volts it should have, and in the attached pins on both sides it had 18.8 volts.
(IMAGE: power jack A1278.jpg)
Until here everything was fine, until I accidentally made contact with the pencil of the multimeter between adapter sense and one of the pins of the PP18V5_DCIN, to which there was a spark and the notebook did not light up more with the form that I had described them. Now, when measuring again cno the multimeter, the adapter sense throws 0.1 volts and the pins PP18V5_DCIN throw 18.8. volts
(IMAGE: power jack A1278 NOW.jpg)
Could someone give me a hand to guide me ?? From already thank you very much!
