Dear Tom and Ray:
There's a sticker on the driver's-side door of my 1990 Volvo 240 DL wagon that tells me to replace or check the air bag by January 2000. Should I worry about this or ignore it? Is there an automotive "sniff test" to see if the air bag is still OK?
Ray: Here's the story, Joe. When your car was made, in 1989 or 1990, air bags were just beginning to become popular. And at the time, Volvo took a guess and figured that it could count on the air bag being good for at least 10 years.
Tom: After all, air-bag systems are built to pretty stringent standards. The bag itself is vinyl, which shouldn't degrade. The contacts are hermetically sealed and made of gold, so they should last forever. The things are over-designed, like A-bombs. Nonetheless, Volvo wasn't absolutely certain how much more than 10 years it would get from an air bag.
Ray: Now, based on 10 years of experience plus some testing, Volvo concluded that air bags are good for at least 15 years. And Volvo might revise its opinion again if experience suggests it can.
Tom: By the way, this is purely a Volvo requirement. There is no federal regulation that requires that air bags be replaced after a certain length of time.
Ray: What the company now wants you to do at 10 years is simply bring the car in for an inspection. And here's the "sniff test." You turn the ignition key to the second position, and you make sure the air-bag light on the dashboard comes on. It should stay on for about 10 seconds and then go off. That means the diagnostic system has run its check and the electronics of the system are in good working order. That's really all Volvo can check without setting off the air bag (hey, it works!).
Tom: If the light doesn't come on, or fails to go out, then the mechanic would check for diagnostic trouble codes in the computer and make repairs accordingly.
Ray: So is it urgent? I'd say if you do the self-diagnostics by checking the air-bag light and it works as it should, you can simply ask about this the next time you go in for service. But if the light fails to come on, fails to go off or flashes while you drive, then I'd go in right away.
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