the switch on the clutch pedal is connected to the ecu and tells the cruise to disengage not to sure if faulty switch would make light flash but you could disconect it and see what happens worst it could do would be that the cruise would not work. i would expect the light out tell tale would inform you, did not know what spec you had but applying logic it must be full spec to have cruise. you can test the switches,you would need two multi meters and connect them to each switch set to resistance then press pedal should both work at same time, you could do it with some wire's and bulb's and holder's and some power but would be hard work. if you did it with one meter you could see that they worked but not in unison. blue switch is purely on/off and makes no difference which way . why are you so sure that the flashing bulb is to do with the cruise ?