Some of the possible causes that prevent activation of cruise control when driving and therefore produce a fault memory entry in the DME:
Main switch not switched on.Throttle grip turned back beyond basic setting.One or several required signals are not plausible, e.g. ABS, CAN bus, speed.Clutch switch 1 (100%) operated.Clutch switch 2 (30%) operated.Front brake or rear brake operated.Kill switch actuated.Side stand folded out with gear engaged.Engine speed too high.Excessive speed difference between the rear wheel and the front wheel.Gear changeSpeed too high or too low.DTC active.
I would write down the measured values of the associated switches, here the left switch unit is the cause of the error due to loose contacts