820-2519 no power/green light. Acok low

[Ryanlen2]

HI,
No power or green light on 820-2915. No liquid on board. ACOK is low.

PPBUS - 12.25V
PP3V42 - 3.483V
ACOK - .037V
ACOK in Diode - .470
pin 27/28 - 20OH
pin 17/18 -3 Ohm

Already changed ISL6259

 

[2informaticos]

ACIN value?
Do you get corect 3V42?

 

[Ryanlen2]

Acin = 3.930v
pp3v42 = 3.483v

 

[2informaticos]

Remove U6901 and check again SMC_BC_ACOK voltage.

 

[Ryanlen2]

Hi.
ACOK still 0.37V after U6901 removed.

 

[2informaticos]

Check R5087; you can force it to 100K...

 

[Ryanlen2]

Getting 115K from R5087.

Thats supposed to be a 470K resistor...


Thanks.

 

[Ryanlen2]

4.97K on pin 1 of R5087. Short on SMC side?

 

[2informaticos]

Try to reflow SMC with good flux...
If doesn't help, remove it; don't forget to check ACOK before resolder other SMC.