820-00239 no power, no image

iClub

Member
Good afternoon, this mac presented image only with the battery disconnected, I analyzed and identified oxidation in the region of UB300, U3100 and the track PP3V3_UPC_TA_LDO that goes to RB310 was broken, I changed the UB300 and made track again, in the tests the mac does not present image and without activity in the USB, the CPU heats up a lot.
I tried another Bios that I found in the badcaps forum, but it didn't work.


Voltage: PPBUS_G3H 13.08v; PP3V3_G3H 3.419V; PP3V3_UPC_XB_LDO 3.3v; PP1V8_UPC_XB_LDOD 1.8v; PP1V1_UPC_XB_LDO_BMC 0v;

Follows the BIOS backup.
 
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