This function indicates if "lap" function (lap number) is active.
When "lap" is not lit up, this means that the function has been switched off.
The "lap" function can be activated using the "lap" function of the setting menu.

Riding mode set indication
Riding style function (riding style change)Backlighting setting function for the instrument panel on Handlebar -
dashboard 2
This function allows backlighting setting of the instrument
panel on handlebar.
To access the function it is necessary to view the "setting" menu page 48, using
button (1, fig. 14) ?"
" or (2, fig. 14) ?" " select the "back light" function
and press ...
Location of elements on motorcycle
(A) injection relay; (b) etv relay (throttle valve operating engine); (c)
radiator fan relay; (d) hands free relay.
(E) ecu; (g) bbs (black box system or central electronics); (f) abs hydraulic
unit with integrated control unit.
Fuses located at the rear left of the vehicle.
...
Refitting the fuel tank
If the fuel tank has been disassembled into its component parts, reposition
all the parts as shown in the exploded view.
In particular:
tighten the screws (13) to a torque of 5 nm +/-10% (sect. 3 - 3, Frame torque
settings).
Refit the tank by inserting its rear side into the pin on the ...