820-3476 No power

BCN_Techs

Member
The macbook entered wet and with sulfate in this area:

1652442188152.png

It has been cleaned, I replace the components and now there is no chime: green - orange led, cpu heats up and there is usb activity.

PPBUS_G3H = 12.57V
PPDCIN_G3H_ISOL = 20.30V
PPDCIN_G3H = 20.30V
PP3V42_G3H = 3.43V
PPVRTC_G3H = 3.33V
PP5V_S5 = 5.15V
PP5V_S4 = 5.15V
PP5V_S0 = 5.15V
PP3V3_S5 = 3.33V
PP3V3_S4 = 3.33V
PP3V3_SUS = 3.33V
PP3V3_S3 = 3.33V
PP3V3_S0 = 3.33V
PP5V_S0_FET = 5.15V
PP3V3_S0_FET = 3.33V
PP1V05_SUS = 1.06V
VCORE = 1.70V

Thanks.
 

2informaticos

Administrator
Staff member
If you have USB activity for sure, do PRAM reset.
This should bring chime back.

Did you test external video?

Do you get 5V at pins 28-30 of J8300, in the first few seconds at least?
LCD_HPD_CONN and DP_INT_HPD should go high at same time.
 

BCN_Techs

Member
PRAM RESET but still the same.

No signal on external monitor.

LCD_HPD_CONN = 0V
DP_INT_HPD = 0V

In power supply, the current goes from 0.02V up to 0.95A directly.
 

2informaticos

Administrator
Staff member
USB power is not the same as USB activity!!!
Your board can't have activity, if PLT_RESET_L stays low.
I wouldn't ask you for external video, or PRAM reset, if you didn't say to have USB activity.

Check pins 7 & 3 of U1950.
 
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