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820 3662, Strange problem

N

Noguinfor

New member
Hey,

Working on 820 3662, no signs of liquid or something like that. I was the first to open it and the board it's very clean!

This machine when i turn it off normally in osx and after that if i want to turn it on, the machine don't turn on... it's necessary to remove the battery, press for 5 sec button power and plug again .. only this way it turn on again!!

Otherwise everything works perfectly.. seems a bios problem. but i need yours opinion to solve this issue for the best way!

thanks
 
2informaticos

2informaticos

Administrator
Staff member
Monitor SMC_ONOFF_L level.
Disconnect keyboard and see how it works using power pads R5115/16.
You may need to remove C4810, to discard leakage.
Also check R5170.
 
N

Noguinfor

New member
Hello,

I already tested without keyboard using power pads and removed C4810 to discard leakage.. Same behavior..

Do you have more ideas for this one? I already have medusa.
 
2informaticos

2informaticos

Administrator
Staff member
I was expecting to get exact voltage for SMC_ONOFF_L signal.
Do you note a drop pulse at PM_PWRBTN_L when trigger SMC_ONOFF_L?

Also check all PCH's RTC signals.
 
N

Noguinfor

New member
Hey guys,

Returning to this one, now i don't have green light and PPBUS = 12.28V

Already replace 2 times SMC and U7100.

SMBUS_SMC_5_G3_SCL - 0.495 - Voltage = 3.4V

SMBUS_SMC_5_G3_SDA - 0.495 - Voltage 3.4V

SMC_RESET_L - 3.38V

SYS_ONEWIRE 3.39V

ADAPTER_SENSE - 3.39V

SMC_BC_ACOK_VCC - 3.4V

Any Advice please.

Thanks
 
2informaticos

2informaticos

Administrator
Staff member
SMC doesn't work.
Check voltages for U5000 (2 OF 2) at page 41.
Pay atention to pull-up resistors for SMC_Txx lines and R5002.
 
N

Noguinfor

New member
Hey, after check all inputs and pull up resistors and compare with a working board i reached the conclusion that SMC have problems.

Replace again SMC and Now its working. But the main problem remains...

"This machine when i turn it off normally in osx and after that if i want to turn it on, the machine don't turn on... it's necessary to remove the battery, press for 5 sec button power and plug again .. only this way it turn on again!!"

Already disconnect all peripherals on board, using power pads but same behavior.

Already replace SMC, U5110.

Already build a new bios with medusa, force Pram no changes!

you have more ideas ??

thank you
 
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