We seem to have a problem with our leisure battery, which I don't know if anyone else has experienced and managed to solve. Whether the battery has been charged via hook-up (more than 24 hours) or by doing a long journey (more than 100 miles), once charging stops the control panel reads 100%. However, after a few minutes this will drop to 90%, and continue dropping by 10% approx every 10 mins, despite having nothing switched on to drain the battery other than the control panel. It usually then sits at 40 or 50%.
Our local VW garage think that this not as it should be, and have tested both leisure batteries to find that they are in good health and are taking the charge as they should. Since VW tested the batteries we have been away camping without hook up for up to 4 days, running just the fridge and occasional lights at night, and the control panel showed a constant 50%.
So it seems that the batteries work - is it possible for the gauge to be faulty, and if so, can it be fixed? Our VW garage had not come across this problem before, and were going to file a report to central VW to find out more. I haven't heard any thing since, so will chase them up.
By the way, our van is a 2008, but we have only had it approx 4 months.
If anyone has any advice, we would be very grateful. Thanks.