Hi, this board came in with no magsafe light. I track down the problem to u7000, q7030, and q7035. replaced all, and magsafe green light come.
a few days later customer came back, no green light. i see ppbus is 12.2v. I have tried replacing smc 3 times.but still ppbus 12.2v and no green light. I test my smc to my sure working board and smc is good. so problem should be on board side.
i noticed smc_bc_acok is low at 0.7v at u7000.
its not shorted, diode mode is 0.473.
so to sum up
I have ppbus 12.2v
pp3v42 : 3.4v
smc_bc_acok 0.7v.
u7000 got proper dcin 16v, acin 4v, vdd 5.1v, and vddp 4v.
any pointer ? thanks..
for info, i have replaced u7000 a few times too, and quite sure its not the isl problem.
the whole board is kinda *not corroded,but oxidized. all probe point is dark.
a few days later customer came back, no green light. i see ppbus is 12.2v. I have tried replacing smc 3 times.but still ppbus 12.2v and no green light. I test my smc to my sure working board and smc is good. so problem should be on board side.
i noticed smc_bc_acok is low at 0.7v at u7000.
its not shorted, diode mode is 0.473.
so to sum up
I have ppbus 12.2v
pp3v42 : 3.4v
smc_bc_acok 0.7v.
u7000 got proper dcin 16v, acin 4v, vdd 5.1v, and vddp 4v.
any pointer ? thanks..
for info, i have replaced u7000 a few times too, and quite sure its not the isl problem.
the whole board is kinda *not corroded,but oxidized. all probe point is dark.