Chosen Solution
I installed a new SSHD after replacing the older HHD that had a SATA failure. When I rebooted with the new drive and ran a diagnostic hardware test, I get an error code 4sns/1/40000000:th00-9.000. I have been searching for a solution and have found a thermal sensor adapter on OWC and others have done a software workaround for fan speed. Any suggestions out there? Thanks
Lets back up here… You stated the system had a SATA failure can you expand on what you mean here. Often this implies the system logic board is having a problem, not the drive. The 21.5" models don’t require the in-line thermal sensor hardware the 3.5" drive require as they use 2.5" drives. I don’t recommend software solutions to over-ride the systems thermal management as we have found they make things worse in the long haul which are more costly.
