A new Mondeo won't have been sitting around for long as production is tighter to customer or dealer order than for Fords of the past. But you can check the seat belt tags. With ‘just in time’ production, seatbelts are unlikely to have been made more than a month before the whole car. Counter-check the date stamped into the plastic under the ashtray, if it has one. Otherwise the date stamps on other plastic components.