1 27" iMac Late 2013 LOGIC BOARD button function?
What is the push button (located just below the SATA connector) function located on the back of the Apple Late 2013 27” iMac Logic board (board number CJ3A - 31PIQMB0070)?
Update (05/24/2021)
After I removed the memory cover I discovered another push bottom near the edge of the board.
The bottom is missing when compared to another Mac 2012 or 2013 board. I see the solder location for the push bottom. I will try to open another 2013.
Meanwhile can you post a picture of a board in which the 820-XXXX number is visible. Visual aid will help with the search for elusive number. I posted another two pictures.
Update (05/24/2021)
I just noticed that the late 2013 27” iMac logic boards with 4 memory chips (I guess 1GB) do not have the push bottom. The logic board with 8 memory chips (2GB) will have the two push bottoms similar to the ones I have posted. I checked on eBay and that seems to be case. I also failed to see on any one of those pictures available on eBay the number 820-XXXX.
Update#2
I also would like to add that after some examination is possible to see the push bottom near the memory banks without removing the logic board. You just need to remove the memory chips and use a flash light to see the push bottom.
Function?????
Update#3
Sorry but my previous comment was not accurate. I forgot that I had removed the memory plastic perforated Black cover from the logic board. I have another IMAC 27 with 2GB of video memory and I can confirm that is not possible to see the second push bottom without removing the screen.
Update (05/24/2021)
I just opened another IMAC 27 late 2103 with 2GB of video memory and I can report that this logic board does not have the push bottoms. I can confirm that this board does not have the T2 chip (software encryption). The encryption can be removed via restore or erasing the drive. I will need to locate another iMac 27 with the T2 chip to confirm that weather or not this is related to encryption. I ma going to add that the logic board for the iMac 27 late 2012 has the four soldering spots for the push bottom. I am wondering if adding the push bottom would allow one to remove the encryption key.
Is this a good question?
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Can you post a picture so we see what you are looking at Adding images to an existing question
by Dan
FYI - You're missing the BR2032 NVRAM battery!
by Dan
@A US - Sadly without a board number it will be hard to locate the boardview to ID the part by its designator to locate it within the schematics to figure its purpose.
Apple often revs logic boards this can explain why some have them and others not.
Keep in mind this level of documentation is also hard to find! What we have is leaked.
So in someways we are Apple archaeologists! Searching for the elusive board drawings and schematics. We may never know!
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by Dan
Are sure you are looking at a 2013 logic board??
The 2012 ~2019 27" systems don't have a T2 chip. Only the 2020 models offered it iMac20,1 & iMac20,2
Why is these buttons such a worry? If you have a problem maybe we can help you.
by Dan