We are confused with our hook-up in our van - 1990 LeisureDrive HiTop. Even though we are hooked up to the mains, at the moment we are only getting the red 'low power' indicator on the Zig CP400 Unit. Does the Zig Unit only measure the charge left in the Leisure battery? I'm sure we have had the green light illuminated when we hooked up before. There is definitely power to the van from the mains as we've just boiled the kettle from the plugs inside the van to test it!
Does the leisure battery get charged through the Zig unit, and therefore if we leave it plugged in, it will eventually illuminate green?

Thanks in advance
Kat N Ive