820-00840-A No power

[PhilipC]

The machine arrived with no ssd and smelling of shampoo but no corrosion.
No idea where to start as I haven't worked on these before.

PPDCIN_G3H = 5V = 19kohm to gnd
PPBUS_G3H = -0.023v = 45kohm to gnd
PP3v3_G3H = 0v = 1.5Mohm to gnd
F7000 = ok
measured current resistors R7020 21 22 and R7060 61 62 all measure within spec

 

[dukefawks]

No corrosion so take it to Apple, this is within warranty. But if you insist, is PM_EN_P3V3_G3H present?

 

[PhilipC]

Its pretty obvious that there has been liquid in the case though, PM_EN_P3V3_G3H = 0V

 

[dukefawks]

Check voltages around U7000, PPVIN_G3H_P3V3G3H, R7075, corrosion there?

 

[PhilipC]

No signs of corrosion

PPVIN_G3H_P3V3G3H = 4.95v
r7075 = 5.2ohm
pin1 = 2.32v
pin2 = 2.28v

C6990 looks to have been replaced

 

[dukefawks]

Voltage on R7075 is probably not right but have nothing to compare. U7000 is suspect. If the ISL9239 is anything like the ISL95530 you are fucked as they have some firmware.