I don't know which it is but there's only 2 or 3 , one for hazards , one main beam one wipers maybe Put the hazards on see which click, flash main beam see which clicks, whatever is left may be intermittent , I'd there a relay on the motor.?
After working on this issue over the weekend Ive found that I don't have an intermittent setting just a slow speed and high speed setting. Its the slow speed setting that blows the fuse.
Sorted the wipers today!! Second hand wiper motor and new switch......apparently I didn't need all four wires in the switch not need for the black with green strip?!?