820-3023

got a 820-3023 with a weird problem. Board turns on perfect with a charged battery.
- Has no audio
-when you plug in magsafe screen turns off (unpluging it screen turns back on)
-get no green/orange light
-will not power on without battery.

tried change i/o board with flat cable same issue.
 

aprendiz

Moderator
Audio is on I/O board, SMC_LID is on I/O board, no green light could be because of a bad I/O board so for me is a I/O board problem, are you using the correct I/O board for this logic board??
 

2informaticos

Administrator
Staff member
Check SMC_LID signal voltage w/ and w/o LIO flex connected.
If drops when you plug the flex, problem is on the LIO, flex, or J4700 connector.
Also check if board turns on without battery when LIO flex is disconnnected; it should start...
 
okay ordered 2 new flex and board still same issue. where should i go from hear?

SMC LID - without power and i/o cable attached 3.042v
SMC LID - with power and i/o cable attached 1.515v
 
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2informaticos

Administrator
Staff member
"SMC LID - with power and i/o cable attached 1.515v"
So your problem appears when you connect LIO board with MLB...
 
yes sir that looks to be the problem but as i have changed the part twice it seems to be a problem within the logic board. any idea where to start looking?
 
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2informaticos

Administrator
Staff member
Look at LIO board schematic, SMC_LID circuit is not complicated at all.
Also check the pull-up resistor from MLB for correct value; you can make it lower, 33-47K.
 
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