820-00165 No Power

opsudhead

New member
hi guys this time i have this board with no power, some corrosion around ISL and U7400 area, after clean the pcb and replace isl i got green/orange light on charger but no fan spin

some measures

PPBUS_G3H 8.60v
PP3V42_G3H. 3.4V
PP5V_S5 5V
PP3V3_S5. 3.3V
PP5V_S4RS3. 5V


with thermal cam i see U3900 and U2800 a little hot

any suggestion?
 
Last edited:

2informaticos

Administrator
Staff member
If you get 5V at L7520, there should be voltage on other coils too; check them all.

ALL_SYS_PWRGD is high?
Inspect Q8150 and U1950 for corrosion.
 

opsudhead

New member
no corrosion, Q8150 and U1950 replaced, measures

L7130. 8.59V
L7520. 5.1V
L7560. 3.3V
L7430. 0.11V
L7630. 1.05V
L7310. 0V
L7320. 0V

ALL_SYS_PWRGGD 0.6V

what about U3900 and U2800 a little hot with thermal cam
 

2informaticos

Administrator
Staff member
Check diode mode to ground at pin 6.
Also check all traces and surrounding components.
Just in case, replace R/C7425.
 
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