The activation of this (amber yellow) "warning" indicates that the engine coolant temperature is high.
It is activated when the temperature reaches 121C (250f).
Note
In this case, ducati recommends stopping and shutting off the engine immediately; make sure that the fans are working.

Low hands free key (hf) battery level
Steering release error - steering still lockedRemoval of the handlebar
Unscrew and remove the screws (3) securing the upper clamp (1).
Remove the upper clamp (1).
Remove the handlebar (4) from its seat on the steering head.
To remove the grips (5), refer to the exploded view at the beginning of this
chapter.
...
Immobilizer override procedure
This procedure makes it possible to "temporarily" turn on the motorcycle if
the hf (hands free) system is not working.
Note
The pin code function must be activated by entering your 4 digit pin in
the dashboard, otherwise the vehicle cannot be
turned on temporarily in the case of a malfunction ...
Rear-view mirrors
Rear-view mirror
Screw
U-bolt
Spring washer
Spare parts catalogue
Diavel abs handlebar and controls
Diavel carbon
abs
handlebar and controls
Important
Bold reference numbers in this section identify parts not shown in the
figures alongside the text, but which can be found in
...