Seatbelt-related Fires Spark Recall of Two Million Ford F-150s

As far as safety recalls go, this one’s pretty sizeable, and it impacts a company that’s seen a lot of money lost on safety recalls in recent years. Ford Motor Company has announced the recall of nearly two million examples of the world’s best-selling vehicle to prevent the seemingly unlikely occurrence of seatbelt-related blazes.

The recall, affecting 1,995,776 trucks in North America — 1,619,112 of them in the United States, is the result of 17 documented fires or reports of smoke in 2015-2018 model year F-150 regular cabs or SuperCrew models sold stateside. Another six incidents took place in Canada.

The fires originated inside the vehicles’ B-pillar, with the seatbelt pretensioner as the source of the issue. While the life-saving device works properly to restrain the front-seat driver and passenger in the event of a crash, it’s what occurs after the device’s deployment that has Ford worried.

According to the automaker, the problem lies in the combination of three factors: the “excessive sparks” generated when the seatbelt pretensioners deploy, the exhaust gasses emitted by the device, and the close proximity of insulation within the B-pillar.

When a pretensioner activates, an electrode ignited a combustible gas at the bottom of a cylinder, pushing a piston upwards. A rack gear connected to the piston engages a gear attached to the seatbelt retractor spool during this upward motion, retracting the seatbelt so that it hugs the occupant tightly against the seat. The device exhausts the gasses generated by the combustion at the same time.

“When sufficient sparks are present, gases exhausted inside the lower portion of the B-pillar by the pretensioners may ignite,” Ford stated. “If this gas ignites, components behind the B-pillar such as insulation and carpet may subsequently catch fire.”

Documents sent to the National Highway Traffic Safety Administration show a lengthy investigation occuring as incident reports piled up. Ford’s Critical Concern Review Group first began investigating after post-collision fires broke out in the B-pillar of four 2015 and 2016 F-150s between April and October of 2017. Despite an analysis of the vehicles, plus subsystem testing, Ford couldn’t come up with a cause.

Further fire reports soon came to the automaker’s attention, with Transport Canada becoming involved in November 2017 after a fire occured on its soil. A joint inspection of that F-150 failed to reveal an ignition source. Ford did, however, determine that the insulation and carpeting used met its own standards. It wasn’t until August, two months after the NHTSA contacted the company with concerns, that the group ID’d the cause.

“A comprehensive series of vehicle level tests was performed. During these tests, Ford observed interaction between pretensioner deployment sparks and exhaust gasses, resulting in momentary combustion, and in some cases, igniting material in the B-pillar area,” Ford wrote in the NHTSA document. “Testing confirmed this potential on both 2015-2017 and 2018 model year systems.”

A field action was approved on August 24th. It’s a simple fix — Ford plans to “remove the B-pillar insulation material and wiring harness tape, and install heat resistant tape.” Owners of regular cab models will see the dealer modify the back interior panel of their pickup cabs.

The recall ( which is free of charge, is expected to begin on September 24th.

[Image: Ford Motor Company]