It seems half the time, after I fix Failure A, that I am able to get out of Failure B after restore. There have been many cases, where the unit came in with liquid damage, clearly a Failure State A type of situation, but the client attempted to restore before sending it, making it into a Failure State B. At this point, if you find you're short on PP3v3_G3H and remove it, you would have to restore again and PRAY that it works. Now you're at Failure State B, it makes it 10x harder to diagnose Failure State A, simply because you can't follow the power structure anymore. At this point, it would fail, and you would be stuck in recovery, let's call this Failure State B. Now you're in Failure State A, and you decided to force the unit into DFU, and attempt a restore. You plug it into another unit, to check if its in DFU mode. If you have a board that comes in, with no power. The problem is, if you fail a DFU restore, you may end up in a different error state than your original issue. There are many things that can cause a DFU restore to fail. Rule out parts or any other board issue that is possible before DFU restoring the unit. The moral of the story here, is before you attempt a DFU restore, for something that could be T2, attempt to rule out everything else before the restore, as you could brick the unit, and be in a worse condition. Obviously this way the unit won't functional properly. I tied IPD_LID_OPEN to SMC_LID_RIGHT to put a bandaid on the situation. I attempted a restore, this did not work. I replaced U4580, which fixed the camera, however the SMC_LID_RIGHT line was brought even lower to. Causing the unit not to fully wake when raising the lid (did respond when lid was closed) The camera also did not work, which lead me to U4850. 2: (820-01958) SMC_LID_RIGHT was low - 1v1 instead of the 1v8 it should be. 1: LID_OPEN_LEFT, LID_OPEN_RIGHT, and IPD_LID_OPEN would all function properly when triggered, however the unit would not sleep when lid closed. Battery stats and settings are stored in SoC Rom and will be reset with Revive, so DFU Revive might be considered as SMC configuration reset.
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