Epson 486SX - Manual (Page 151)

Select Y to cancel formatting (and check your backups) or N to
continue.
If you continue with formatting, you see:
Format started.
Head
: n n n
Cylinder
: nnnnn
The head and cylinder numbers decrease as the program
progresses.
When formatting is complete, the program flags any bad tracks
and you see a series of messages like these:
Format finished.
Flagging bad tracks...
Cylinder is
nnnn,
head is
nn
Format completed.
Press Enter to return to the menu.
Press to return to
the Hard Disk Format Menu.
Option 2, Destructive Surface Analysis
You can perform a Destructive surface analysis of your hard
disk to accurately locate any bad tracks and flag them, if they
are not flagged. The test operates by a complex process of
writing, reading, and verifying information on every track of
the hard disk, except for tracks that are already flagged as bad
tracks.
Physically Formatting a Hard Disk A - 9