2019 Macbook Air 820-01521-a shorted PP3V3_G3H and flashing led on logic board

Hello,

By removing the U7800 chip, short goes away. Installed another chip from a donor board same thing. Anyone run across this before? This is the only chip that immediately gets hot under infrared camera, rest of the board does not heat up when I force voltage on the PP3V3_G3H.

The only other Item I did find for sure bad was C7806. It was shorted to ground replaced it, still have direct short on PP3V3_G3H.

Any help would be appreciated.

Thanks
 
Update for reference.

Installed another U7800 chip short now gone. Still only 5v at the charge port. LED light stays on solid now also. Darn, thought that was it, but no.

My methods of checking voltages in order they are on the diagrams is bad for me. I should have checked core voltages and shorts on the core lines first and I would not have wasted so much time on this board.

PPVCC_S0_CPU 0v----- diode mode .2----- ohm check at C1131 .2 ohms----- dead short, great :(

So injected 2amps voltage @1.5v at C1131 and the only thing that reacted under infrared was the intel chip. Removed chip, short gone!!! Bad intel chip. So if I would have jumped over to the core voltage checks first and found bad intel chip, obviously would at that point put this board in the parts bind and moved on and not bothered you guys on this one. Sorry, my bad. I try to only to ask questions that I'm really having difficulty with. So I hope this will at the least help someone else in the future.

Thanks for your time.
 
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