Chosen Solution
Hi there! I have two a1989 MacBook Pros, one of which has an issue in the logic board and does not transmit video to the internal display. I wanted to swap out the boards in these two machines, as the functional one has an US layout topcase (dinged in places), while the one with no video has PT layout and in much better condition. I’ve been reading that the T2 chip may brick the MacBook Pro, and wanted to confirm prior to dismantling the Macs… they are both fully original and with no aftermarket parts, so will it work? If yes, will I have to swap the fingerprint sensor between cases too? Thanks in advance for the advice. Cheers, Pedro
Brick the machine? I doubt it. I have done a similar thing before just to test some components on a MacBookAir 2020 (Intel) without issue. But you will likely lose some functionality. Things like True Tone display may not work properly and I’m not sure about Touch Bar functionality, but T2 regulates those functions and both display and top case are paired to the logic board. The Touch ID sensor is also paired, so if you do not transplant it with the logic board it will only function for power and not fingerprint sensing. But board itself should function just fine.
Yes, you can swap out your logic board, but are you sure the issue is the logic board and not the display? Assuming the display is working, they you would need to swap out the TouchID button with the logic board as the two are married and can’t be separated. As to True Tone issues @flannelist pointed out, that’s not true here. As the display is a part thats been calibrated vs a fresh part that has not, so it should be OK here. Often I find the small circuit board (T-CON) which is part of the display assembly get damaged. Unless you’ve got a cracked display this is the likely cause of your lack of a working display. To prove that plug in an external display if that is working then the display is bad. I would be doubly sure before proceeding as you may end up with still a busted system in the end.
