We had exactly the same problem as Midgely posted on 11th April 2016 and the Ford Dealer initially said there was no fault. However, after the dealer fitted a new battery which went flat overnight it was found that a part of the stereo unit which appeared to close down when everything was switched off actually came on again and caused the rapid drain. A replacement stereo was suppliued and fitted under warranty. It has solved the problem and, in addition, we always make sure that all lights, heater, fan, stereo etc are switched off before we switch off the ignitions and lock the car - this ensures that the battery is not having to fire-up these accessories when next we come to start the engine.