Is the SSD part of a fusion drive in iMac A1418 (EMC 2883) replaceable?

Apple's Fusion drive consists of a blade SSD and a separate mech drive; the two are linked by software to act in concert.

However, it is not clear if you can replace the blade SSD in the 2015 model.

—First, have you looked to see what is required to get inside a sealed-case iMac? Some service providers will not work on them. Trying to open the case may damage parts that can only be fixed with a new logic board, and some components are close to an exposed power supply.

—Second, the biggest supplier of upgrade parts for Macs, OWC, says their blade SSD upgrade kit for Fusion-equipped iMacs does NOT work on the Late 2015 model. It's not clear if the blade SSD, like the RAM, is soldered in place in the specific model. From the OWC site:

NOTE: Aura Pro X2 SSDs can only be installed in 21.5-inch iMac models that came with a factory-installed SSD or Fusion drive. Aura Pro X2 is not compatible with iMac16,1 or iMac16,2 (Late 2015).

[ref page: https://eshop.macsales.com/shop/ssd/owc/imac-21.5-inch/2013-2019

—Third, the most popular how-to site only suggests replacing the roto-drive with a slower SATA 6G 2.5-ich form factor SSD assuming you get the case open without a visit form the Grim Reaper.

I recommend calling or emailing OWC to ask why their blade won't work in the 2015 model. You can find their support contact page from the above link.

Allan Jones wrote:

—Second, the biggest supplier of upgrade parts for Macs, OWC, says their blade SSD upgrade kit for Fusion-equipped iMacs does NOT work on the Late 2015 model. It's not clear if the blade SSD, like the RAM, is soldered in place in the specific model. From the OWC site:

NOTE: Aura Pro X2 SSDs can only be installed in 21.5-inch iMac models that came with a factory-installed SSD or Fusion drive. Aura Pro X2 is not compatible with iMac16,1 or iMac16,2 (Late 2015).

[ref page: https://eshop.macsales.com/shop/ssd/owc/imac-21.5-inch/2013-2019

—Third, the most popular how-to site only suggests replacing the roto-drive with a slower SATA 6G 2.5-ich form factor SSD assuming you get the case open without a visit form the Grim Reaper.

I believe the problem is there may be no PCIe blade connector for the SSD, or the slot is not active if the iMac does not ship with a PCIe blade SSD from the factory.

I also believe the SSD connector is on the other side of the Logic Board, which means the majority of components inside the iMac need to be removed or as least loosened and slid to the side a bit. It is a delicate procedure that requires a bit of skill & patience. I know that it is very easy to pinch & damage a cable in this process, plus there are several difficult to reach cables & connectors when trying to disconnect & reconnect the Display Assembly (those cables & connectors are very fragile & easily damaged). It can also be tricky lining up the Display perfectly since you must deal with the annoying adhesive to hold the Display in place. The hard drive is even difficult to remove since the cable is not long enough to connect/reconnect the SATA Cable to the 2.5" drive (the hard drive can be seen as soon as the Display is removed).

I recommend calling or emailing OWC to ask why their blade won't work in the 2015 model. You can find their support contact page from the above link.

Always good advice. Plus look at the OWC upgrade installation video for your iMac on the SSD upgrade page of OWC. Keep in mind the video may make the process look easier than it really is.

Allan Jones wrote:

OP says this shipped with a Fusion drive so I assume it has a blade SSD. already. However, because the 2015 21.5" model is so odd, I do not know if the SSD is socketed or soldered like the RAM. The "other" how-to site only mentions replacing the roto-drive in 2015 models with a 2.5-inch SSD.

It has a connector on the MLB for a blade style SSD.

HWTech wrote:

I believe the problem is there may be no PCIe blade connector for the SSD, or the slot is not active if the iMac does not ship with a PCIe blade SSD from the factory.

Good morning!

OP says this shipped with a Fusion drive so I assume it has a blade SSD. already. However, because the 2015 21.5" model is so odd, I do not know if the SSD is socketed or soldered like the RAM. The "other" how-to site only mentions replacing the roto-drive in 2015 models with a 2.5-inch SSD.

I may drop a note to OWC about this when I get some other Monday stuff off my desk today.

Then I guess the OWC blade solution for other iMacs has some other incompatibility with just the 2015 models. I'll check.