820- 2330 A - All the rails checked out okay but wont turn on

menatwork

New member
The board was working fine in another assembly, as soon as I installed in the customer system something caused the board to go bad and does not turn on, All the rails checked out okay but wont turn on.
this is second motherboard I installed and caused issue for me. I know there is a problem in the assembly i should not use that assembly anymore, but I like to fix the board.

I did not used keyboard but I shorted power pad.

Please advise

Rails Checked

PPBUS_G3H - OK
PP3V42_G3H - OK
PP3V3_S5 - OK
PP1V2R1V05_S5 - OK
 

larossmann

Administrator
Staff member
Replace C7771 with a regular capacitor, not a tantalum one. It will work one second and not work the next, it can't be trusted.
 

larossmann

Administrator
Staff member
and of course obviously try turning it on with nothing hooked to it but a fan and see if it comes on.
 

larossmann

Administrator
Staff member
This board is eight years old. I genuinely believe the voltage is randomly dropping when you hit the button. Worse has happened to me before
 

larossmann

Administrator
Staff member
Is PM_PWRBTN_L moving when you press power? Is SMC_ADAPTER_EN high? Is the green light green? I wouldn't expect much from this at this point
 

larossmann

Administrator
Staff member
Nah. LCD is so far away from where we are right now. :( Do you have 32 KHz for RTC on the crystal? This is really old and could be literally anything, and without any more hints this one probably won't go far. :(
 
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