Hey, just got a 03 plate active sport and the fan speed control on heater was very hard to turn, so messing about with it ive managed to break it and now cant set the speed, its stuck on no.3 but can still turn control just it doesnt do anything. How do i fix it? do i need a new contol for just that fan speed or new heater unit and apart from fiat where could i get a cheap one?? cant find any on ebay cheers guys