Coachman 2014 laser charger buzzer noise

Rhysfell

hi we have had our caravan in storage for a few weeks the battery was flat when we came to collect it so did an overnight charge and had it on electric hook up all weekend, came to use motor mover when packing up and keeps resetting itself after a couple
of manoeuvres. Upon returning home the same day I dropped it back on the electric and getting a constant buzzing from the electric box, when I pull the fuse for battery it stops? Any ideas anyone.regards Rhys