Ford has some problems with the current Fiesta. The Detroit-based manufacturer is recalling 154.604 Fiesta units, 2011-2013 model to be more specific. The cars affected by the recall were built in Mexico between 3 November 2009 and 21 September 2012.

The reason for the US-only recall is the passenger side curtain air bag. This might not deploy in the event of a side impact collision when the front passenger seat is empty.
 
Although the side curtain air bag system was designed to suppress the side curtain air bag in such a case, that information is not explained in the owner’s guide for these vehicles as required by federal regulation.
 
An occupant in the right rear seating position will not have coverage from the side curtain air bag in a side impact collision when the front passenger seat is empty, increasing the risk of injury to the right rear occupant.
 
US Ford dealers will reprogramme the restraint control module software, free of charge.

Source: Ford