Macbook A1989 (820-00850)

[Instafixx]

No turning On.
Stuck at 5v.

Looks like someone already injected voltage somewhere before.
PPBUS at 12.3V
3v3_G3h is present too.

Machine recognised in DFU Mode. But gets stuck during DFU Revive/Restore

3V3_G3G_SSD0 diode readings are normal. Checked Voltage for more than 20 Seconds. It is stable.

 

[2informaticos]

All SSD and G3S voltages present?

 

[Instafixx]

which other SSD voltages do you need ?

 

[2informaticos]

SSD has 3 main voltages: 2V7, 1V8 and 0V9.

 

[Instafixx]

L9080/1 is 0V
L9030/20/21 is 0V

 

[2informaticos]

"Looks like someone already injected voltage somewhere before"
Where?

 

[Instafixx]

I couldn't find. There was solder at the ground point so I am assuming voltage was injected

 

[2informaticos]

Compare diode mode readings on all secondary power supplies with good board.

 

[Instafixx]

Lines Checked
PP5V_G3S
PP5V_S5_LDO
3v3_g3h_rtc
3v3_s4sw_sns
1v2_s0sw.

All are fine

 

[2informaticos]

Didn't touch the secondary coils?

 

[Instafixx]

Which ones are the secondary coils ?

 

[2informaticos]

All big coils, doesn't think?

 

[Instafixx]

L7702 .085
L7430/20/10 .010
L7210/20 0.009
L7270 .025
L8102 0.143
L8100 0.253
LB700 0.506
L7600 0.473
L7660 0.430
L7030 0.495
L8410 0.860
L3500 0.499

 

[2informaticos]

What about L9080?

 

[Instafixx]

L9080 is 0.394

 

[2informaticos]

Which voltages from above mentioned lines appear on the board?

 

[Instafixx]

I get only L7030.
Rest all are 0V

 

[2informaticos]

"Rest all are 0V
------------------
3v3_G3h is present too"
???

 

[Instafixx]

My bad. L7660 has 3.3V. Missed it totally.

 

[2informaticos]

What DFU errors did you get on revive/restore?