hi all, i got this mainboard from a repair shop telling me it didnt power on. when i got the board, i see that green-orange light on charger was present, ppbus was present, 3.3 s5 were present but all other volts were missing. that board got water spill around U3310, but the previous shop cleaned the board and replaced some caps, so it is much harder for me to see if some other component is bad.
after some measurement, i see that if i remove u8030, i got 5volt s0, ddr volt and all vots coming (except 3.3 s0 ofcourse and u8030 got volts in, enable pin and no vout obviously). u6100 pin 1,2,3,5,6,7,8 got 3.2 volts, i removed jtag as on some forum i see one dude having that exact same problem like this and solved the no power when u8030 is soldered, but without jtag i have still same problem.
without u8030 i have fan spinning at max,
now i see ppvcc_s0_cpu resistance to 001 on multimeter in diode mode and if i put 1 volt on cpu coil i see it absorb current and cpu get hot.
now that sounds like a cpu short to gnd, but to be sure that my problem is the cpu, i would like to know if someone else encountered my same problem, i replaced u8030 2 times and u1950 once, but still no go.
if i solder back u8030, 3.3 s4 is 0.5 volt.
if i remove u8030 and connect magsafe, then inject 3.3 on s0 rail ( that take 0.07A) all s0 volts stop working.
if u have any expecrience i would like to learn more about that problem.
also all other voltage like rtc ecc ecc are present., but with u8030 i lose most of enable volts.o
after some measurement, i see that if i remove u8030, i got 5volt s0, ddr volt and all vots coming (except 3.3 s0 ofcourse and u8030 got volts in, enable pin and no vout obviously). u6100 pin 1,2,3,5,6,7,8 got 3.2 volts, i removed jtag as on some forum i see one dude having that exact same problem like this and solved the no power when u8030 is soldered, but without jtag i have still same problem.
without u8030 i have fan spinning at max,
now i see ppvcc_s0_cpu resistance to 001 on multimeter in diode mode and if i put 1 volt on cpu coil i see it absorb current and cpu get hot.
now that sounds like a cpu short to gnd, but to be sure that my problem is the cpu, i would like to know if someone else encountered my same problem, i replaced u8030 2 times and u1950 once, but still no go.
if i solder back u8030, 3.3 s4 is 0.5 volt.
if i remove u8030 and connect magsafe, then inject 3.3 on s0 rail ( that take 0.07A) all s0 volts stop working.
if u have any expecrience i would like to learn more about that problem.
also all other voltage like rtc ecc ecc are present., but with u8030 i lose most of enable volts.o
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