820-3787 - Fan spins for a second.


I have n 820-3787 with pretty minor spill damage (see pics.) There was a short on PPVIN_S5_HS_COMPUTING_ISNS at U7330. I replaced U7330 and the short is gone. Fan spins once for about a second and that's it. Magsafe light is on. Normal green to orange switch. SMC reset is normal, turns green for a few seconds.
PPBUS_G3H: 12.56V
PP3V42: 3.4
PP3V3_S5: 3.3V
PP3V3_SUS: 3.3V
PP3V3_S4: 0
PP5V_S5: 5V
PP5V_S4: 0V

SLP_S3 and SLP_S4 are both 0V

When I check 3V3_S4 it will start at 3.3 while fan is spinning and then slowly work it's way down to about 0.20V. Same goes for PP5V_S4. Drops down from 5V after fan stops. Not sure where to go from here. Let me know if there's any other information that would help.



On the topic of shorts, I'm measuring 0.001 in diode mode on PPVCC_S0_CPU. On a 2015 15" board I'm measuring about 0.014. Is it possible I still have a short? It's always a little tricky to tell if there's a short on the CPU lines because the resistance to ground is always so low, but this seems too low.
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Does anyone have any thoughts on this? Is this the way a CPU would go bad? Would it most likely be internally shorted? I've removed R7300, R7310 and R7320 to isolate the issue down to the PPVCC_S0_CPU line. The top left corner (with pictures above as reference) of the CPU gets hot when viewed through infrared camera when I send 1V through the PPVCC_S0_CPU line.