EC480Control Panel-Waste water problem

Just started our hols. We are at present on a CL site near Dover. Tomorrow we take the ferry to France and the start of our journey to Slovenia via Germany and Austria, returning through Italy (the Dolomites).We have an issue with the waste water showing full even though the tank is empty. The alarm immediately greeted us when the Sargent EC480 control panel was switched on. Before we left there were odd green half full positions even though tank was empty. I think there maybe a thread about this somewhere, but I can't find it. Any help with this issue would be much appreciated. It's not a major problem just a little irritating.
Thank for any help.
Pete

Try removing the connector on the rear of the display panel, wait a few minutes then reconnect, see if that helps
Personally I never take any notice of the thing and empty the waste most days

Thanks for you advice. I have always left the tap open and drain the waste into a wastemaster container, so I don't normally need to monitor the panel, but it should still work and be fit for purpose especially on a 15 month old motorhome!
Pete

Totally agree, but those panels cant always be believed.  Have a look through postings (including my own and mods done to ours)on the forum over problems of accuracy.
Its a shame really cos Sargent are a good company that offer good customer support.