Outofwhack
Member
Dead MacBook with customer saying it was working but wasnt charging and no light on magsafe.
No evidence of liquid damage.
5volts drawing 0.9amps, PPBUS 6.8volts with spot on U7700 reaching 70 centigrade.
Fuses removed and back to 12.3v but
PP3V8_AON was reaching 3.0v and had impedance of 38ohms.
Replaced U7700 due heat spot, also replaced C5897 and sound amplifier that had contributed to low impedance on PP3V8_AON.
PP3V8_AON DM now 0.400
Can these multiple failures on components powered by PP3V8_AON indicate 3.8v had gone much higher or can this just be a longevity thing?
PPBUS and PP3V8_AON now correct voltages but I see most voltages from the PMICS getting periodically interrupted at say 2Hz.
PP1V8_S2SW_VDD1 reaches 0.33 and cuts out repeatedly at similar rate.
Thermal camera shows U2780 pulsing at similar rate but PVDD1_PWR_EN is constant 0v.
I cant decide whether not getting to 20v is the problem or is U8100 PMIC damaged like U7700 appeared to be and needs replacing?
Help!!!
No evidence of liquid damage.
5volts drawing 0.9amps, PPBUS 6.8volts with spot on U7700 reaching 70 centigrade.
Fuses removed and back to 12.3v but
PP3V8_AON was reaching 3.0v and had impedance of 38ohms.
Replaced U7700 due heat spot, also replaced C5897 and sound amplifier that had contributed to low impedance on PP3V8_AON.
PP3V8_AON DM now 0.400
Can these multiple failures on components powered by PP3V8_AON indicate 3.8v had gone much higher or can this just be a longevity thing?
PPBUS and PP3V8_AON now correct voltages but I see most voltages from the PMICS getting periodically interrupted at say 2Hz.
PP1V8_S2SW_VDD1 reaches 0.33 and cuts out repeatedly at similar rate.
Thermal camera shows U2780 pulsing at similar rate but PVDD1_PWR_EN is constant 0v.
I cant decide whether not getting to 20v is the problem or is U8100 PMIC damaged like U7700 appeared to be and needs replacing?
Help!!!
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