Macbook A2337 Stuck at 5V Amps Cycling Between 0.01 to 0.45

Instafixx

Member
Board Clean.
PPBUS is Fluctuating between 0V to 12.2V.

Did thermal imaging when connected to charger.
Found something near U7700 heating up. It's either R8001 and L7800.

Diode mode readings of both are as per the Openboarddata.

R8001 resistance across pins is 1M Ohms
 

2informaticos

Administrator
Staff member
R8001 can't overheats; is 1 Mohm resistor.

U7700 is first suspect if L7800 overheats.
Just in case, try replacing the coil first.
 

Instafixx

Member
Replaced U7700 . Still the same.
L7800 still heats up.

PP3v8_vddmain diode mode is .220 - is that ok?
 
Last edited:

Instafixx

Member
PPBUS is stable at 6.6V.
Removed FUSE - Get stable 12.29V.
I thought bad fuse so replaced it. still the same.
Have good diode mode readings of .560 on both pins.
 

2informaticos

Administrator
Staff member
That's the problem.
Not easy to fix, as you don't have short there.
Check all components around U5700 and adjacent MOSFETs.
 
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