Just done a journey with childseats in the back and no bums in them and the car assumed that there was a person in the backseat not belted up and proceeded to warn me of such for a good 4 minutes.... Never an issue in C7 and this will do my nut in if it is constant. Childseats are isofix but no sensor in car to identify them as such... Any ideas, fault or 'characteristic'?