Mac Mini bottom cover late 2012

[sfxguy]

Hi, I have a late 2012 Mac Mini that I put a 128gb ssd in to mac a fusion drive with the stock 1TB platter drive.

To make a long story short, it has worked fine for years, then the SSD started failing causing problems.

I took out the bad ssd, replaced it with a 500gb ssd, and left the 1TB drive in, not creating a fusion drive this time.

Everything works great, runs just fine, but the back cover won't go back on. I have lines up the white dots, turned it to the black dot, and it just spins and falls off.

Anyone have any thoughts on what I am doing wrong or might have broken? I came off fine, just won't go back on.

Thanks for any tips.

 

[treekram]

My 2012 Mini only has one white dot on the black cover. You line it up with the empty dot on the chassis and turn until it lines up with the black dot on the chassis.

If that doesn't work, on the inside of the cover are 3 black plastic "islands". Each should have small plastic protrusions toward the top of the island which will prevent the cover from falling off. On my Mini, 2 of the 3 islands have 2 protrusions, 1 has a single protrusion (with maybe a very slight 2nd protrusion). Maybe the plastic protrusions broke off. On the chassis itself are three screws where the head is about 2mm tall and where there is a space between the screw head and the chassis where those plastic protrusions on the islands will slip into. If you're missing a screw, then that could also explain why the cover is falling off. Or if the screw was tightened too much, that needed space between the screw head and chassis won't be there (however, I don't think the screws can be tightened that much). Or, if you mixed up these screws with the screws which attach the WiFi antenna plate to the chassis (these 2 screws should screw down flush to the antenna plate). Or, if some part is sticking out more than it should - that could be the fan or the WiFi antenna plate.

It's not uncommon for the WiFi antenna plate to not fit quite correctly as it can be a tight fit. That can cause a problem. I had this problem for years but just didn't screw one of the interior screws which attached the antenna plate to the logic board. (This didn't prevent me from screwing in the screws which hold the cover to the chassis, though.) It was only when one of the old threads about this issue was resurrected that I found a solution to that.

If there's a problem with the island(s) or the screws, then you would need to get a replacement or just tape the cover to the chassis.

https://www.ifixit.com/Guide/Mac+Mini+Late+2012+Hard+Drive+Replacement/11716
Note in step 2, the 3 screws which are used to hold the cover in place are seen towards the outside of the circle.

 

[sfxguy]

OK that is what I thought, I had those 3 plastic bits left over and I thought that was where they went, but they were not attached to the back plate. It looks like they are supposed to be glued onto it??? But they stayed on the screws when I took off the plate this time. Does that sound right?

I have it taped now, but if a new back plate comes with those plastic bits I might just order one, they are so cheap...

My 2012 Mini only has one white dot on the black cover. You line it up with the empty dot on the chassis and turn until it lines up with the black dot on the chassis.

If that doesn't work, on the inside of the cover are 3 black plastic "islands". Each should have small plastic protrusions toward the top of the island which will prevent the cover from falling off. On my Mini, 2 of the 3 islands have 2 protrusions, 1 has a single protrusion (with maybe a very slight 2nd protrusion). Maybe the plastic protrusions broke off. On the chassis itself are three screws where the head is about 2mm tall and where there is a space between the screw head and the chassis where those plastic protrusions on the islands will slip into. If you're missing a screw, then that could also explain why the cover is falling off. Or if the screw was tightened too much, that needed space between the screw head and chassis won't be there (however, I don't think the screws can be tightened that much). Or, if you mixed up these screws with the screws which attach the WiFi antenna plate to the chassis (these 2 screws should screw down flush to the antenna plate). Or, if some part is sticking out more than it should - that could be the fan or the WiFi antenna plate.

It's not uncommon for the WiFi antenna plate to not fit quite correctly as it can be a tight fit. That can cause a problem. I had this problem for years but just didn't screw one of the interior screws which attached the antenna plate to the logic board. (This didn't prevent me from screwing in the screws which hold the cover to the chassis, though.) It was only when one of the old threads about this issue was resurrected that I found a solution to that.

If there's a problem with the island(s) or the screws, then you would need to get a replacement or just tape the cover to the chassis.

https://www.ifixit.com/Guide/Mac+Mini+Late+2012+Hard+Drive+Replacement/11716
Note in step 2, the 3 screws which are used to hold the cover in place are seen towards the outside of the circle.

 

[treekram]

It looks like there are 2 fasteners (not screws) which attach each island to the back cover. I would guess that superglue wouldn't work well and alignment would be a problem. Maybe the fasteners can be re-attached but I don't think that will work well either so if you can get a back cover cheap, that would probably be the best solution.