Fault codes
Dds: horn diagnosis -> short circuit to ground (s.C. Gnd).
Dashboard: the error "claxon" (horn) is shown on the service display. The eobd warning light activates.
Wiring diagram

Db dashboard connection, s horn button. 5 Blue/white - b/w, 1 red/blue - r/b, db 19 purple/black - v/bk.
Location of connections and components

Location of left hand handlebar switchgear set connection.

Location of horn with relative connection.

Pin numbering for wiring harness side dashboard connector.
Note
Check integrity of electric circuit - short-circuit to vdc = with dashboard on, using a voltmeter, a voltage is measured between the wire tested and ground.
Check integrity of electric circuit - short-circuit to ground = with the battery cables disconnected, using an ohmmeter, continuity is detected between the wire tested and ground.
Check integrity of electric circuit - open circuit = with the battery cables disconnected, using an ohmmeter, no continuity is detected between the two ends of the wire tested.
Low beam lights not working
Turn indicators not workingChecking and topping up coolant level
Check coolant level in the expansion tank on the right side of
the vehicle.
Steer the handlebar completely to the left and check that the
level is between the min and max marks on the side of the
expansion reservoir.
Top up if the level is below the min mark.
Unscrew the filler plug (1) ...
Removal of the throttle twistgrip
Peel back the rubber sleeve (a) protecting the throttle control cables.
Undo the screws (b) of the throttle grip (6) and open the command.
Disconnect the throttle grip cables (10) by unhooking the cable ends (c) from
their seats.
Remove the throttle twistgrip (6) from the handlebar.
...
Tft - parameter setting/display
Warning
Any adjustments to the instrument panel must only be
carried out when the motorcycle is stationary. Never operate
the instrument panel controls while riding the motorcycle.
At the end of the check, the instrument panel always
displays as the "main" indication the odometer (to ...