820-3536 Water Damage - Green Light - No Power - No fan spin

[dam1inc]

Have an 820-3536 thats water damaged, has a green light no fan spin.

PPBUS_G3H 12.3v
PPBUS_S5_HS_COMPUTING 12.3v
PPBUS_S5_HS_OTHER5V 12.3
PPBUS_S5_HS_OTHER3V3 12.3
PPDCIN_G3H_ISOL 16.8v
PPDCIN_G3H 16.8v
PP3V42_G3H 3.42v
PP5V_S5 0v
PP5V_S4 0v
PP5V_S0 0v
smc_pm_g2_en = 3.4v
smc_tx_l = 0v

someone worked on this board before and from what i can tell U7501 and U7100 have been replaced or reballed.

 

[aprendiz]

PPBUS on 12.3V is not ok, check resistance on U7100 between pins 17/18 and 27/28, voltage on pin 10 and 11.....

 

[TCRScircuit]

So someone messed with the ISL probably because they were hoping for a easy one and not a dead SMC. Check if pins 10 and 11 of the isl are shorted. If so, it's going to be either the ISL, SMC or D6950 (May have got the number wrong, use brain to figure out which one I mean that pins 10 and 11 of the ISL lead to ) If they are not shorted, Try a new ISL. If it still doesnt work, Take the edge bonding off the SMC and give it a reflow with flux and some heat. See if it works and go from there.

 

[dam1inc]

PPBUS on 12.3V is not ok, check resistance on U7100 between pins 17/18 and 27/28, voltage on pin 10 and 11.....

resistance between pin 17/18 is 4.1ohms and between 27/28 is 20.6ohms and pins 10 and 11 have 3.42v

 

[JohnB8812]

Yep flux and heat SMC and see

 

[dam1inc]

Yep flux and heat SMC and see

reballed SMC, same thing so replaced SMC and same thing PPBUS_G3H is still a little short and missing pp5v_s5, s4, s0

 

[JohnB8812]

Try new ISL

 

[dam1inc]

swapped it twice

 

[JohnB8812]

There must be a broken trace then somewhere on the data lines. I had one the other day where the trace between the SMC and the pullup resistor was broken. Also possible one of the pullups is bad or blown

 

[dam1inc]

super green here lol, so pullup resistor for this board is R7120?

 

[JohnB8812]

Check R5380 and R5381 as well as the traces between them and the SMC.

 

[dam1inc]

Both 3.42V and traces look fine...scratched the top of the trace right before it gets to SMC and is also 3.42 on both

 

[JohnB8812]

Might be a dumb question, but are you measuring with just the board and no battery? If so, the only thing I can think is the SMC you put on is bad.

 

[dam1inc]

Yes board+magsafe only. Ill try another SMC right now

 

[dam1inc]

slapped on another SMC and no change

 

[dukefawks]

Are you using SMCs from a donor board?

 

[dam1inc]

Are you using SMCs from a donor board?

Yeah, ordered a bunch of boards and have been pulling them off. So you think maybe the SMC's im pulling are all crap?

 

[dukefawks]

Nope, just needed to know you weren't using "new" SMCs.

Is charger light turning orange? Is PP3V3_S5 present?

Got a scope?

 

[dam1inc]

Oh no I read your posts about "new" SMCs

charger light is only green

PP3V3_S5 = .006v

and I just bought a scope but i dont know how to use yet

 

[TCRScircuit]

Are you using the same SMC or just some random one?