Water in diesel filter light.

Hi all,
I'd appreciate help with the following please.During driving today in my TD5 Disco,dash warning light for water in diesel filter light came on.Ok,so changed filter and thoroughly cleaned and dried plug and sender unit on bottom of filter.Before connecting everything up,did the following checks.1-Plug disconnected,ignition on and no light showed-expected.2-Plugged in sender unit free of the filter and light came on and that definitely was'nt expected!Recleaned plug/socket on sender again-same result.Anyway,by now was freezing to death so fitted evertning back,bled the system and engine runs fine but obviously the blasted light is still on.
Does a fault code need to be cleared?I would have thought that for such a simple problem,just changing the filter would have sorted it.However,nothing these days surprises me any more-so advise would be most welcome please.
Thanks-Adrian

Sender is bolloxed or not properly clean. It is only a fancy bit to to terminate the cable. Any water sits at the bottom of the filter and shorts across the contacts and brings the light on. If the light stays off when the sender is unplugged it must be either water or the sender.

Hi,
Thanks for your advice.I actually stripped the sender unit and meticulously cleaned it,using compressed air etc.Made no difference.
BUT, on start up the following morning,light out!After about 10 miles came on again,then few miles later,off again.After about 20 miles of this,it went out and has stayed out ever since!
I have also now been told that they are known to be troublesome-you're telling me!Many thanks for your help-appreciated.
Adrian

The sedimentor is a PITA - even when it looks OK. I put a new one on a couple of years ago

T

I removed mine. Saves the grief.