If you have an Explorer Group van like ours an inaccurate water reading is one of the endearing features of the breed - and, I have to say, from our point of view, not at all serious once you get used to it
In every van I have had the gauges have been wildly innacurate. If they work at all it's just a matter of knowing what any particular reading means. My water tank goes from full to half just filling a kettle and then stays on half till its nearly empty when it suddenly drops. My waste tank reads empty until its about to overflow when it reads a quarter full. You soon get to know how long a tank will last.:thumb:
The best thing to do when touring is to fill up and dump whenever the opportunity presents itself. A bit like all of us as we get older.