Hi everyone, I am a newbie so please forgive what is probably a daft question ! Can I charge the caravan's battery by using the lead from the car towing electrics? I would have thought so, but when plugging it in with the engine running, the battery charger light wont come on to indicate it's taking a charge. Caravan is an Abbey Expression, less than a year old. Am I doing anything wrong, or is it taking a charge without having to put the charger switch onto on?