820-00850 Has voltage but no CPU

[bjf]

This had some type of minor spill but I'm struggling to find much sign of it. The little bit of corrosion was cleaned before it got to me. It gets 20V, has PM_SLP_S4_L, has 5V on PP5V_MAIN_VCCSA but no CPU power. There is a very slight amount of heat on the CPU. I'm not finding any shorts though. Any idea where to go next?

 

[2informaticos]

Post voltage for all big coils...

 

[bjf]

PP3V3_G3H: 3.3V
PP5V_G3S: 5V
PPBUS: 12.62V
CPUVR_SWSA: 1.05V
PVCCIO_PHASE: .95V
P1V2_PHASE: 1.2V
PP0V9_SSD0: .9V
PP1V8_SSD0: 1.8V
PP2V7_NAND0: 2.7V

Nothing on PPVCC_S0_CPU or PPVCCGT_S0_CPU

 

[2informaticos]

VCCGT appears only under grapichs load.

You could have a dead CPU now, if someone reflowed it before.
Check powers and enable signal for CPU power supply.
Be sure DDR power supply works too, as other voltages which are not on coils; Power FETs, page 78.
You can also try full new BIOS; not only clean ME of your board.