Charging battery whilst towing problems

[Norman_374579033]

I own a Avondale Rialto 2001 model and have had no problems unti last week.I replaced my leisure battery to a 110AH in order to power the mover. Spent 5 days in Glastonbury with no hook up. I connected the van to the car in order to boost the battery, but on starting the car the voltage indicator in the van dropped from 12v down to 9 volts whilst engine running. this might sound a silly question but is this normal?.I then changed the 12S plug following the wiring diagram but am still getting the same results, with some ticking noise in van/car when switching engine off. Can anyone help because I'm at my wits end. Thanks.

 

[Damian]

When you start the engine,with the van 12S connected, it triggers the habitation relay, which is what you hear ticking, to shut off all 12v services except the fridge 12v supply and charger circuit to battery.

 

[Norman_374579033]

Thanks for the valuable information,thought I was going crazy, I have just bought a volt meter and checked that the battery was charging which it was, but still couldn't work out what the ticking/clicking noise was, but you have confirmed it Cheers