Item description:

HDDChecker is a basic disk diagnostic tool meant for testing the health of your PlayStation 2 console's Harddisk Drive unit.
It was conceived and constructed because I didn't want to see anymore poor SCPH-20400 units being cut open, just to have the disks within them taken out for testing. >_>
It'll also be useful for those people who need to check the condition of their HDD units, but don't have a working IDE port on their computers to connect the disk to.
It has the following features:
Detects and lists the model, serial, firmware and S.M.A.R.T. status of HDD unit 0 (Primary Master).
Performs a surface scan of the disk.
Supports 48-bit LBA disks up to 2TB.
Performs zero-filling of the disk with large blocks.
With the surface scan, bad sectors found might be remappable*.
Checks for damage to the APA scheme and PFS partitions.
Optimizes the partitions on the HDD to reclaim space.

*Writing to a to-be-remapped sector (those hard-to-read sectors, as recorded by the disk) may cause them to be remapped.
However, this might not be the case for all disks.