Imac A1311 MLB 820-3126-A dead

[erguro]

Dear technicians and engineers

First of all, merry Christmas, I need to fix a mid 2011 Imac A1311 with MLB 820-3126-A
It,s my first time with imacs I heard that is very common SMC failures and Ati radeon hd6750m gpu failures

MLB is dead no start no chime only high speed fans so I think is a smc failure, could you help me to start checking mlb? Now I have all the info, schematics and brd files but It will be great with a first steps tips in mlb check, I tested psu voltages and are ok

Thanks in advance

Best regards

 

[erguro]

any idea will be apreciated

thanks

 

[ThienBui]

any idea will be apreciated

thanks

we have support you in inbox.

 

[erguro]

we have support you in inbox.

Yes but not to this question

 

[ThienBui]

Nobody can say exactly, all needs to try.
You can't fix it with just a few questions.
Let's start testing from the most basic components....

 

[erguro]

Nobody can say exactly, all needs to try.
You can't fix it with just a few questions.
Let's start testing from the most basic components....

That's exactly what I ask to you, how to test smc? obviously because I don´t know the answer

 

[ThienBui]

That's exactly what I ask to you, how to test smc? obviously because I don´t know the answer

SMC is can not check, you need try one BIOS new.
you only can reset SMC where mac have display or ignore it if the Mac has no display...

 

[erguro]

SMC is can not check, you need try one BIOS new.
you only can reset SMC where mac have display or ignore it if the Mac has no display...

MLB is dead new BIOS didn´t worked for me

 

[ThienBui]

MLB is dead new BIOS didn´t worked for me

check haware.

 

[erguro]

check haware.

wow thanks that's an awesome idea, SMC is hardware or is a cat?

 

[ThienBui]

wow thanks that's an awesome idea, SMC is hardware or is a cat?

SMS System Management Controller"
you can buy chip new and change where want.
example: Please check right name above motherboard for you and buy right.
https://ru.aliexpress.com/item/F2117LP20H-F2117LP-BGA-SMC-chip/32393640108.html

 

[Ricardo Marcelo]

olá , amigo faça um reballing apenas no SMC, vai resolver seu problema !