hi, recently purchased this van and have two questions that hopefully you can help me with. above the door it has the AC75 battery panel, to the left of this and seperate there is a switch that is illuminated, does anybody know what this is for?. Also the van was sited for the past 2 years and had a permanent water feed to the inside water tank. i think that they have altered the water pipes and pumps, unfortunately this isnt listed in the handbook, so ideally could do with a schematic diagram of this. any help would be appreciated