Ducati SPORTTOURING ST4s 2005 Manuel D'utilisation Et Entretien page 211

The fuse located on the side of the battery (fig. 99)
protects the electronic regulator. Remove the fuse cap (4)
to expose it. A blown fuse is identified by the interrupted
inner filament (5, fig. 100).
Important
Switch the ignition key to OFF before replacing the
fuse to avoid possible short circuits.
Warning
Never use a fuse with a rating other than specified.
Failure to observe this rule may damage the electric
system or even lead to fire.
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