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So, I've been struggling with this one over the last few days.
* Replaced ISL > No change
* Replaced SMC > Didn't work (possibly faulty SMC)
* Replaced SMC with 3662 version and clean BIOS > Same behaviour (this one is just for testing, as I don't have any more 3787 donors)
I'm guessing some...
with batt connected
w/o batt connected
12.2 V rising to 12.7+ V
12.57 V steady
Difference over R9398 (GPU Phase 2)
0 V >> 0 A draw
Difference over R9399 (GPU Phase...
Ok, I started testing for the suggestions above, but noticed the heatsink got hot real quick. Turns out phase 1 of the GPU is pulling ±35A from the start. GPU problem? I'm confused as to why that VR would even start at this point during POST/boot.
This board works fully (in limp mode / 800MHz) when the battery is disconnected. When the battery is connected it chimes repeatedly, so at the end of the chime, it chimes again. A different battery produces the same result. Replaced ISL6259, didn't help. Any thoughts? Could this be GPU related?
Things tried so far:
* Boot with wired connection
* Boot with touchbar, touchID and screen disconnected
* Full reinstall
Will boot into safe mode. Had some corrosion on the touchbar side of the logic board.