Will my airbag and seatbelt work if I'm hit while sitting in a parking lot?

Dear Car Talk

Dear Car Talk | Mar 01, 1993

Dear Tom and Ray:

I love your column, and I have two questions. 1) If you're sitting in the drivers seat in a parking lot with the engine off, and you're hit head on, will the airbag activate? 2) How can I check my seat belt to know for sure that it will hold me if I crash? I have tried to pull it as fast as possible, but it doesn't catch.

TOM: Good questions, Dick. Airbags need electricity to detonate. So most of them WON'T inflate when you're sitting in a parked car.

RAY: Here's how they work. When the ignition switch is on, the cars electrical system provides the power. When the car is shut off, electricity is stored for airbag detonation for between thirty seconds and several minutes, depending on the car. The reason for that is in an accident, the battery connection could be severed early in the crash, and you'd still want the airbag to inflate seconds later and protect you.

TOM: The only exceptions, we've been told, are Ford Motor Company products. Ford airbags are reportedly powered all the time, and WILL detonate even if the car is parked and turned off. We should stress that we don't have any first hand experience with Fords in this regard, although my brother is testing a '93 Continental as we speak, and the week is still young.

RAY: As for the seatbelt, the reason you can't get it to catch is because it doesn't respond to how fast you pull it, like seat belts used to in 70's. Modern seat belts use a pendulum in the seat belt housing at the bottom of the door frame. When the car stops suddenly, the pendulum swings forward and locks the belt. This design allows you to move comfortably at all other times, and keeps you belted tightly in a panic stop or accident.

TOM: If you want to test the pendulum, go out to a parking lot, get going about 20 mph, and then brake hard. You should feel the belt lock as you're stopping.

RAY: When you do this, you might also want to aim for a parked, unoccupied, late model Ford. That way, if you wait too long before braking, we'll also find out if their airbags are really powered all the time!

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