Less than a week after Ford finally issued a recall for nearly 400,000 vehicles that may contain malfunctioning door latches, the car manufacturer is adding another 156,000 of the same vehicles to the recall roster.

The company announced today that it would expand its recent door latch recall to include an additional 156,000 model year 2011 to 2014 Fiesta, and model year 2013 to 2014 Fusion and Lincoln MKZ sedans after receiving a request from the National Highway Traffic Safety Administration, which has been investigating the door latch issue for more than seven months.

The expansion bring the number of Ford-made vehicles that may contain doors that inadvertently open while the car is in motion to 545,906.

According to Ford’s recall notice, the door latches in these vehicles may experience a broken pawl spring tab, which typically results in a condition where the door will not latch.

The manufacturer says it is aware of two allegations of soreness resulting from an unlatched door bouncing back when the customer attempted to close it, and one accident where an unlatched door swung open and struck an adjacent vehicle as the driver was pulling into a parking space.

Ford’s recalls come less than two months after NHTSA upgraded its investigation into the malfunctioning latches to include the Fusion and Lincoln MKZ vehicles. In addition to increasing the scope of the investigation, regulators upgraded the probe to an engineering analysis – a step that can sometimes lead to a recall.

Prior to Ford’s recalls, NHTSA said [PDF] it had received 207 reports related to improperly latching doors. Sixty-five of those reports claimed that the door or doors opened inadvertently while the vehicle was in motion.

When NHTSA originally launched an investigation into the Fiesta models last September, the agency had accumulated 61 reports of potential door latch failures, of which 12 allegedly occurred while the vehicle was in motion. Since then, Ford has provided the agency with 451 additional reports and 1,079 warranty claims related to door latch failures.

Ford previously said it did not believe that a latched door experiencing this condition would inadvertently unlatch and that there are many overt warnings associated with a door that does not latch.

Still, regulators said back in March that the “rate of occurrence for this failure is comparable to other door latch failure investigations” and that the agency “questions the effectiveness of warning signals given the number of complainants alleging that the door(s) opened while the vehicle was in motion.”

Ford Expands Door Latch Safety Recall in North America [Ford Motor Co.]

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