Hello Just taken the switch completely apart, your idea of water within the switch was spot on, about a tea spoon full or two dripped out of the switch assembly. Got on to my local ford dealer and was given a price of £24 ish !! I thought that £24 was way over the top so I nicked the wife’s hair dryer to dry the switch out and then resealed the rubber cover with silicone seal bath seal so far so good. If anyone feels like me about the price and has time on their hands you could obtain a replacement micro switch for about £5 from rswww.com, looks to me very much like part number 197-7