820-4924 starts only in smc bypass

ielectron

Member
it had small water damage, it was powering on before, it had a broken screen also

i cleaned it out now it wont power on only with smc bypass

only small corrosion i see is C1910 but the ppvrtc_g3h is 3.3V present, C5021 next to smc

i removed those caps, same
reflowed SMC, same
 

ielectron

Member
smc not enabling 3.3v at u7501 but if i keep reconnecting the charger than sometimes it does, and the board kinda turns on but only with 0.5A and the fan wont start, in smc bypass it turn on with 0.7A and fan

i replaced u7100, same, the 10 ohm resistors are good and the area is not water damaged
 

ielectron

Member
ok it works with the battery only, i tried the board out of the chassis, after cleaning it works fine, those tricky a1502 laptops, most of them works without the battery, this one needed it
 
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