820-3437 board . some time turns , some time dont

[turbo]

got this board some time turns on some time , dont ... no water damage or physical damage at all. clean board..

its turns on most of the time when its out of mac.. when i put it in most of the time it does not want to turn on .


when it turns on battery charger everything is ok....

 

[arghhh]

Remove JTAG and check for corrosion around smc reset circuitry.

 

[turbo]

which one is JTAG ?

 

[arghhh]

https://www.youtube.com/watch?v=a67p6pziKz8

 

[dukefawks]

Need info. Voltages when it doesn't turn on etc. I bet this was dropped or flexed.

 

[turbo]

when does not turn on , here is the voltage


PP5V_S4RS3=0v
PP3V3_S5_REG_R=3.3v

SMC_RESET_L= 3.4v

S5_PWRGD=3.4v

PM_SLP_S4_L=0v

PM_SLP_S3_l=0v ( no s4 , so there should not be s3 any way )

pls tell me which other voltage should you need ..

 

[dukefawks]

Could be anything. If this was no liquid and 100% sure about that. Only thing to check is voltages on C1300 and 1303.

 

[turbo]

C1300 and c1303 3.3v when not turns on

 

[larossmann]

I bet some liquid got in the trackpad which you can't see which is causing the trackpad to reset the SMC and keep it from turning on. Unplug the trackpad cable and see if you ever have the issue of it not turning on when this is unplugged. You would be turning it on now by plugging in the charger.

 

[turbo]

No Title

louis when board is on the table still doing same thing , some time turns on some time dont

 

[dukefawks]

Could be anything, time waster board.