Can I start by saying, kingdavid54 you are indeed a true king! I've only gone and fixed it thanks to your advice.
I took the boot/trunk to bits and found enough water to keep a couple of goldfish happy!
I removed the clm and dried it out then cleaned up the corrosion on the board and the connectors with Servisol and a toothbrush. Put it back together and hey presto it works.
Thanks everybody for your input. Great forum. Divorce off the cards and it's even stopped raining. Happy days.
I'm sure there are loads of posts on this problem but if anyone needs advice on what I did please ask while it's still fresh in my noggin.
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