OK. That probably discounts the cause of the cruise not engaging being a failed clock spring but not to rule it out. Is yours a manual or auto? There’s a switch on the clutch pedal (if manual) which disengages cruise if the clutch is depressed, if that switch is faulty Ithink it might prevent cruise from working. Alternatively, linkage with speed sensors on wheels, through the BIU might inhibit cruise. Others probably need to chime in here as I’m running out of ideas. Lastly, the actual switch on the end of the stalk might be u/s.