Ducati MONSTER 821 2016 Owner's Manual page 123

Note
When the LAP function is active, the FLASH
button takes on the dual function of high beam
"FLASH" and LAP timer start / stop (new lap start
indication).
Note
Upon Key-OFF, the "LAP" function status is
saved to restore it upon next Key-ON.
Note
When the battery is off, if the LAP function is
active (ON), it is automatically disabled.
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