I'm sorry this question seems to have been asked multiple times before, but ether I'm missing something or my situation is different than previous posts. So no 12v power on hook up. Arrived at site last night. Plugged in electric hookup. I have 240v but no 12v. The charger light is on on the ems2000 unit. The in line fuse to the Battery is OK. Have switched the car/van switch to middle point but no voltage shown on the internal voltmeter. Leisure Battery is reading 12.1v when checked with a volt meter but no power from the battery. With the car plugged in I have 12V and every thing in the caravan works as it should. Ignition on and all stops so think habitation relay is OK. With ignition off and the caravan switch moved from caravan to car a buzzing /clicking noise can be heard from the front of the van. So any one any idea what this could be and what to test next. The van is a Stirling searcher 2003 twin axel. Many thanks for any help. P38paul