The activation of this (amber yellow) "warning" indicates that the hands free system has detected that the battery that permits the active key (1, fig. 62) To communicate and turn the vehicle on is almost discharged.
Note
In this case, ducati recommends replacing the battery as soon as possible as described in the paragraph "replacing the active key battery" (page 88).

Hands free key (hf) not recognised
High engine coolant temperatureReplacing the battery in the active key
Only use 3 volt cr 2032 lithium ion batteries.
Note
The keys do not need to be reprogrammed after
replacing the battery.
Remove the metal part of the battery.
Use a large sized coin to pry open the shells of the plastic grip
(2? coin) as shown in fig. 65.
Important
Insert the coil on ...
Warning indication (alarms/signals)
The instrument panel activates in real-time some warnings /
malfunction that are not dangerous for the correct operation
of the vehicle.
At key-on (at the end of the check) one or more "warnings"
are displayed if they are active.
When a "warning" is triggered, the indica ...
Removal of the cooling system hoses and unions
Loosen the clips (21) that secure the radiator/thermostat sleeve (40) and the
radiator/plug sleeve (24) to the water
radiators.
Loosen clips (25) and (43) that secure the breather pipe (26) to the
radiator/plug sleeve (24) and to the left radiator.
Loosen the clips (34) securi ...