820-2915 Power on & off loop

macfix

Member
Hello Everybody

Working on 820-2915 come my desk not green light problem. Some one tried fix board . No voltage on PPBUS_G3H and replaced U7000 nothing changed.
After removed F7040 green light come back, then i inject 12.5V PPBUS_G3H line fan spin 3 sec. than stop loop .

Note: When i connected battery green or orange light not come only battery disconnected green light turns on.

Now where can i check next step?
 
Last edited:

macfix

Member
F7040 pin 1 is 12,5V when removed fuse. But when put back fuse no green light. ( No short a ground PPBUS_G3H line )
 

macfix

Member
Hello again
After replacement Q7080 green light is ok and put back F7040. ( Also battery charging turn light orange ) but still power turn on off loop continue :(
 

dukefawks

Administrator
On/off does not spell anything good. Was the ROM messed with? Inspect for missing components. Could be many things.
 

macfix

Member
Yes original 85W charger (tested 17" Macbook PRO without battery its runs ).

Re flash SPI but nothing changed :(

PPVRTC_G3H is 3v stable , PM_SLP_L is 3.3v ( when 3.3V fan spins) 1 sec. later turns 0V maybe give any idea about next step
 

macfix

Member
Yes know its could be anythings but spend too much time and now want to solve problem...

No CPU VCore Duke
 
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