820-00239 Won't turn on. Liquid damaged.

iClub

Member
This mac suffered oxidation in the U9300, UB300 and Q9401 region, where the u9300 was shorted, I took it out and tested it, but it doesn't show PPBUS.

Voltage: PPbus 0V; PP20V_USBC_XB_VBUS_F 0V; PPDCIN_G3H 5.116V shows oscillation; PP3V3_G3H 3.4V; LDO rails showed ideal values in diode mode; PP1V8_UPC_XB_LDOD 1.8V; PP3V3_UPC_XB_LDO 3.37V; PP1V1_UPC_XB_LDO_BMC 0v, oscillating ;
 

2informaticos

Administrator
Staff member
Isn't strange to get PPDCIN without VBUS?

All USB-C ports have the same behaviour?
Q9401 was shorted?
What is the actual resistance to ground at L9400?
 

iClub

Member
P2V7NAND_SW 0,391V
PPVIN_2V7NAND_LB 0,448V
L9400 0,6 Ohm
FB200,F3001,FB201 and F3000 5v, sorry, now the voltages are showing up.
The machine is without the u9300, does this influence the PPbus?
 

iClub

Member
L9400 0.6 Ohm this value is the resistance of the component. The value of P2V7NAND_R is 0.395V diode-scale.
I want to know if there is voltage at PPBUS_g3h when the u9300 is off the board ?
 

2informaticos

Administrator
Staff member
Post basic voltages for U7000; listed many times on the forum.
Probably SMC doesn't communicate with U7000, nor with CD3215 chips.
LDO voltages for U7800?
 

iClub

Member
U7000diode modeVoltage
PPVIN_G3H_P3V3G3H5674,78v~
TBA_AUX_DET6411,27v~
TBA_VDDA4685,040~
TBA_VDDP4665,038~
TBA_MPM_DET6373,41V
HPWR_EN_L6413,38v
CHGR_AMON6396mV, sem pulso
CHGR_BMON63973mV, sem pulso
SMC_RST_L636
U7800
PP3V3_PMICLDO411
PP5V_PMICLDO462
PP5V_PMICLDO_R462
 
Top