Does Anyone Know?

[cabinetman]

There are those that keep cars a long time. How long is an undeployed airbag good for? There doesn't seem to be a good check other than setting it off, and then you have an expensive fix. Some of the cars have been around since the early 90's.

I don't know of disclaimers associated with airbags, like "replace every 10 years". This begs the safety, reliability and liability question of that old airbag just tucked away.
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[KenBurris]

I found this at justanswer.com

Every time you turn the ignition to run the airbag computer tests the system and if it senses a problem the airbag warning light will stay lit. If the system proves out during the self check the light will be turned out.

Read more: http://www.justanswer.com/questions/...#ixzz0gab5iWZS

[phi1l]

I've had my Toyota Since 94, & the air bag hasn't failed yet

[Uncle Cracker]

Mine works every day... Stuffing it all back in there is a real PITA...

[LinuxRandal]

Where electrical parts seem to have a problem, is corrosion at the connectors, sensor/module/relay, sticking in one mode (both should trigger a fault code), occasionally a broken wire (replacing something close and pinching it). Now as for the explosive, remember in the gulf war, we were using shells, that were WWII era. These are more stable explosives and should last longer.

Your biggest issue, that is controllable, is keeping drinks, and liquids, from around the steering wheel. On the passenger side, don't overfill your glove box (stuff can fall behind). Door, be careful if your modifying them for speakers.

[JSUPreston]

My first car didn't have airbags, unless the wife was riding with me.

Thank you, I'll be here all week.

[Woodwerker]

I have a 94' Lexus with 200,000+ miles and the Lexus Tech said the bag will be good for as long as the car is around

[MilDoc]

Do a Google search on "airbag life."

The "expected" half-life is 10 years. The "self-check" ONLY checks the electronics, NOT the airbag function. Doing that would mean blowing the bag! Same as home fire sensors that check ONLY the electronics, not the sensors.

And "half-life" means that 50% will fail after 10 years.

I have no idea if a dealer could check "true function," but I doubt it. IMHO the only way to do that would blow the bag!

[LCHIEN]

the lifetime of a item is based on the shortest lived components. In the case of the airbag, it might be the electronics or it might be the chemical elements that expand the bag rapidly, or it might be the plastic and fabric components.
Probably the electronics is good for at least 10 years if not severly corroded or exposed to moisture. But the electronics is one part that is testable so the SRS check makes it not a replace on time kind of item, rather you replace when it stops working. The hard part of the electronics to test is the acceleration sensor, fortunately that's a solid state part with no moving parts and very reliable.

The other items, the chemicals and the plastics/fabrics degrade with time. There's no set rate of degradation because these depend on temperature and storage conditions. Generally warmer temperatures accelerate the deterioration of chemicals and fabrics as does exposure to UV. Things kept cool dry and dark survive longer.

The car manufacturers advise checking and possibly replacing airbags at 10 or 15 years. but mostly you can only check the electronics the bags and chemicals are sealed and designed to open one and once only on impact and not be rapackable after examination or use.

Sadly, as i always state, expiration dates are hardly a practical way to do things. Batteries, food, drugs, air bags, they all degrade at a slow rate. A battery with an expiration date of Mar 2010 does not go dead on February 28, 2010. it has a slow rate of discharge an on march 1, 2010 it might be 3 years old (1095 days) and have .05% less energy than it had the day before. And it still might have 2/3rds or 3/4ths of its energy left.

Drugs lose potency and chemicals lose effectiveness. Fabrics, threads lose strength. Almost all follow an exponential decay.

Generally where a manufacturer puts an expiration date, that's when under the worst storage conditions the product will have lost some percentage, maybe10 or 20% of its properties.

What that means to you is that at expiration, it will still have 80 to 90 percent effetiveness, and closer to 100% if stored in reasonable conditions.

Since airbags cost around $500 to 1000 each, replacing two or four airbags in a ten year old car just isn't going to happen given that people who own 10 year old cars own them because of economic reasons, usually. Fortunately, 90% effective airbags still do a good job; they are overdesigned typically.

I don't think i'd spend a lot of time worrying about 10 year old airbags.

[cabinetman]

Generally where a manufacturer puts an expiration date, that's when under the worst storage conditions the product will have lost some percentage, maybe10 or 20% of its properties.

What that means to you is that at expiration, it will still have 80 to 90 percent effetiveness, and closer to 100% if stored in reasonable conditions.

Since airbags cost around $500 to 1000 each, replacing two or four airbags in a ten year old car just isn't going to happen given that people who own 10 year old cars own them because of economic reasons, usually. Fortunately, 90% effective airbags still do a good job; they are overdesigned typically.

I don't think i'd spend a lot of time worrying about 10 year old airbags.

I'm about 50% convinced that out of 100% of the vehicles that fall into the 10% to 20% loss of properties may be in a percentage of vehicles that have 80% sustainable properties. Of that percentage if I have a vehicle that loses more than that like 50%, only a small percentage of that loss like maybe 25% may be in chemicals, and 75% in electronics, or the other way around. If more than 10% of the effectiveness is sustained, then 90% is an expected performance, which may only be effective in 50% of the situations in which an airbag would save a life. If 100% of those people in the 50% category don't care or don't want to worry, then hopefully a small percentage of those situations requiring a good airbag will be in the 90% group.
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[Uncle Cracker]

Do a Google search on "airbag life."

When I did that, it came back with a bio on my ex...

[cabinetman]

When I did that, it came back with a bio on my ex...

That reminds me of ex #1. Whenever I blew into her ear, she would thank me for the refill.
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[woodturner]

The "self-check" ONLY checks the electronics, NOT the airbag function. Doing that would mean blowing the bag!

One would think that, but I did a consulting job a few years ago to design a sysmte to test squibs (the explosive charge that fires the airbag).

The squibs are electrically detonated with a wire that is embedded in the explosive and heats up to fire it. One common manufacturing defect is that the explosive did not completely flow around the wire. If not enough of the wire is touching the explosive, the charge will not fire.

The squibs are tested by applying a LOW signal and looking at the reflection. When the wire is in contact with the explosive, the electrical characteristics of the wire are detectably different.

But I still always thought of the Bugs Bunny cartoon, where he is testing the artillery shells by hitting them with a hammer and marking them "dud".

[RayintheUK]

Uh-oh, I'm off on a tangent again!

This reminds me of my visit to Martin Baker's factory in Uxbridge, circa 1988, where they make ejector seats for fighter aircraft. They make each component of the seats themselves (apart from the 'chute) and once installed, they're never tested until the pilot pulls the black and yellow elevator handle. So far, they've saved 7,300 lives and - as far as I know - haven't had an operational seat failure yet. They retrofitted their seats into the Starfighter, which originally fired downwards, I believe.

The VTOL aircraft gave them a sizeable challenge when they came along, as their seats must have a 0-0 capability (put the crew member on the end of a brolly from 0 feet altitude and 0 knots). If a VTOL quits while hovering, they adopt the attitude of a breeze block and there is a need to overcome the fall-rate of the aircraft before the pilot starts to rise. To this end, they doubled the size of the rocket tubes in the VTOL Harrier jump-jets! The G-forces were intensive at the top of the curve and although pilots survived, they tended not to dig their garden for a while.

Their web site still fascinates me after all this time. Sorry for the wander off-topic.

Ray

[SHADOWFOX]

My first car didn't have airbags, unless the wife was riding with me.

Thank you, I'll be here all week.

Almost spilled my coffee on my dress shirt and dress pants when I read this. Hilarious!!!!

Kind regards,