Took the car to local Fiat garage who hooked it up to diagnostics. Waited nearly three hours, not a clue! Then they phoned Alfa garage whilst looking under the car. Turns out that there is some sort of switch under the clutch pedal which has a 'plunger'. Apparently this 'plunger' can deactivate the cruise control and has some wiring behind it. They checked this on the suggestion of Alfa and found that the 'plunger' was sticking causing something to bend which in turn trapped or loosened wiring to other bits of the car and not activating the cruise control. Quick job then to loosen off, free any trapped wiring connector, realign the plunger, grease and lubricate. Car working great now, and no warning lights!! Hopefully cured!