DETROIT — Ford is recalling more than 154,000 Fiesta subcompacts to fix a problem with the side air bags.

The company says that if the front passenger seat is empty, the side air bag won’t inflate to protect rear-seat passengers in some crashes.

Ford says it doesn’t know of any crashes or injuries linked to the problem.

The recall affects Fiestas from the 2011 through 2013 model years.

Dealers will reprogram the computer that controls the side air bag so it inflates even if no one is in the front passenger seat. The repair will be done for free.