[SOLVED]820-3437 Fan spin only when the SMC is warm

[Adan]

I'm working on a 820-3437 board. It had no green light. After some mesures, I conclued to change the SMC. I did change the SMC : green light, fan spin while the SMC area still warm. But after the board get cool the fan does spin anymore but I still have the green light. So I changed again the SMC, and I still have the same issue after the board get cool. Does somebody has a clue please ?

 

[dukefawks]

Diode mode on pin 2 of R6061? Are you sure it is not just a flaky fan, that is common.
Did you use an SMC from exact same board?

 

[Adan]

Diode mode on pin 2 of R6061 : 0.715
The fan is all right, even then, the board does't turn on at all, no shime, no screen.
I used two differents SMC from the same board, same issue : fan spin turn on when the SMC still warm

 

[Adan]

I checked the soldering of the SMC, it look's bad. I'm going to do it again.

 

[Adan]

I found the solution. SMC soldering was good, the problem was comming from dirt on Q3088. So I took of this element, clean the pads, soldered back. And now it's working. Thanks Dukefawks for the advices.