From the 2015 manual:
"Adjusting spring preload for rear wheel with Dynamic Damping Control
Make sure the ground is level and firm and place the motorcycle on its stand.
Switch on the ignition.
Start the engine to avoid discharging the battery.
When you make changes to the DDC system settings the ignition has to be ON, because only then are the electric valves active."
'10 Ducati Streetfighter 1098S
'07 Ducati 1098S Tricolore
'05 Ducati 999