820-3332 at boot and PCH heating.

[iClub]

Good afternoon, this mac suffered oxidation, I performed the cleaning in the tests off in the middle of the boot. I cleaned the ME region. the system boots, but with intermittence. I analyzed the board again, I identified the missing c2450, I put another one in place, but I'm still locked in the logo.
In the ASD test, I diagnose with no defect.

PPbus_g3h 12.61V; PP3V42_G3H 3.42v; Vcore 0.85V;

 

[2informaticos]

Did you resolder U8900??

 

[iClub]

Yes, twice.
The Mac used to go up the system before, I passed to a technician here, he kept trying to turn on the machine without the coolers, after that the system didn't go up anymore.
I cleaned the ME region, without success.

 

[2informaticos]

Check for knocked of components, or broken traces.
Also heat BGA chips, with quality flux; 10-15s at 180-200 degrees, just to burn eventually accumulated crap.

 

[iClub]

had a lot of thermic folder under the chips. but it still hangs up in the middle of the boot.

Could you clean this ME region for me, please?

BAKCHP.bin

drive.google.com

 

[iClub]

It worked, I tested it with another external macOS, Thank you!