Automatic Seat Belts and Why They Failed

If you were born before 1990, you probably remember at least one vehicle in your life with automatic seat belts. The belt was typically mounted on a track, with one end connected in the normal seat belt connection point and the other on the door or above it. When the door was open, the belt would move forward, but when the door was closed, the belt would move into position around the occupants. A motor was typically used to accomplish this movement, though non-motorized systems were used in some vehicles.

In most vehicles with automatic seat belts, the system only operated on the shoulder belt; the lap belt had to be fastened manually. A few vehicles had both automatic lap and shoulder belts.

It sounds like a great idea, a vehicle that automatically fastens the seat belt. And yet no one has used them in over two decades. As far as automotive features go, automatic seat belts were short lived.
Volkswagen was first to offer the belts on their 1975 model Golf; General Motors followed suit, offering the belts beginning in spring 1978 on the Chevy Chevette.

But it wasn't until the second half of the 1980s until most vehicles got automatic seat belts. On July 11, 1984, NHTSA issued a rule that required all cars to be equipped with automatic seat belts or a driver airbag. The rule was phased in from the 1987 to the 1990 model year, during which time a certain percentage of cars manufactured by each manufacturer were required to meet the new standard: 10+ percent in 1987, 25+ percent in 1988, 40+ percent in 1989, and all vehicles from the 1990 model year and later. The standard didn't apply to light trucks (such as vans, minivans, pickup trucks, and SUVs).

Problems began to emerge with motorized seat belts. Some thought that only the automatic shoulder portion of the belt had to be used, greatly reducing the belt's effectiveness and putting them at risk of "submarining" (sliding under the belt), which begged the question "If you have to fasten a lap belt anyway, why have automatic seat belts?" The belts were often intrusive and uncomfortable and made it more difficult to get in and out of the car. Many automatic belt systems could not accommodate child seats (keep in mind that during this time period, late 1980s to early 1990s, babies often rode in the front seat) Not surprisingly, consumers preferred airbags to automatic seat belts.

A few companies largely bypassed the automatic seat belts by using driver airbags from the get-go to meet the standard, most notably Chrysler Corporation, who equipped all of their 1990 model cars that were built in the US with a driver airbag. Luxury cars also were rarely equipped with automatic seat belts, also typically going the airbag route. But most car models were afflicted with automatic seat belts at some point.

By the 1992 model year, about half of all new cars had an airbag, and automatic seat belts were rapidly losing popularity. On December 18, 1991, the Intermodal Surface Transportation Efficiency Act was passed, which included a clause that all new cars would have to have dual airbags by the 1998 model year, and light trucks by 1999. Market pressure continued to push airbags; by the 1995 model year, most cars had dual airbags. It was rare for an airbag equipped vehicle to be equipped with automatic belts. The 1996 Ford Escort was among the last vehicles to be equipped with automatic seat belts.

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