
Open OnyX, and type your administrator password.

Click the Verify icon, then select the S.M.A.R.T. Status tab.

Click the Check button to immediately verify the S.M.A.R.T. status of the startup disk.
You can use OnyX to check the S.M.A.R.T. status of the startup disk and to provide the option of running this verification upon opening OnyX. This option performs a diagnostic that can prevent an HD failure. Most disks include S.M.A.R.T. hardware (Self-Monitoring Analysis and Reporting Technology), which tests and monitors the drive.
Warning:
- Checking the S.M.A.R.T. status of the startup disk is only possible with an ATA or Serial ATA disk. The FireWire and USB disks do not (yet) allow this in OS X.
- OnyX cannot check the S.M.A.R.T. Status of a RAID Set or Fusion Drive.
- If FileVault is turned on, checking the S.M.A.R.T. status will not be possible (Message: The S.M.A.R.T. status is not supported.). If you turn off FileVault, restart the computer again before checking the S.M.A.R.T. status of the disk.
Open OnyX, and type your administrator password.
Click the Verify icon, then select the S.M.A.R.T. Status tab.
Click the Check button to immediately verify the S.M.A.R.T. status of the startup disk.
The S.M.A.R.T. Status tab of the Verifying pane displays the S.M.A.R.T. status and the date of the last verification.
By default, OnyX asks whether you want to check the S.M.A.R.T. status of the startup disk when OnyX opens. You can choose to automatically check it, or check it, or do nothing by selecting the corresponding option in the Advanced tab OnyX Preferences pane.