Life & reliability of Airbags?

drjones · 9th April 2009, 14:02

Hi, I would like to know whether there is any method to check the airbag condition and whether we need to kind of refill the gas cartrige at times. I know the " Go crash your car " method of checking guys, I wanna know something without the crash part.
Dr.jones

vikram_d · 9th April 2009, 14:54

The only test that can tell you whether the airbag is working fine is the "Blowing It Up" test. The gas cartridge in an airbag is a one time use only device. It cannot be refilled. Also the airbag itself once deployed cannot be re-used.

visu03 · 9th April 2009, 16:08

Even I am keen to know how to check if the airbags in the car are working fine apart from blowing them up. I know about the light in the dash, but I think there must be other ways.

Here's the back ground for my interest on the topic
I heard (may be a rumor) that once a car was sent to the dealer after a minor accident where the airbags got deployed. The dealer repaired the whole thing and in the process hasn't replaced air bags. Instead he "adjusted" the wiring so that the sensor thinks that the air bag system is working fine. Next time the car meets with an accident air bags do not deploy. Luckly the owner survived and insurance team found that the airbags were not replaced after the first accident. The whole thing is hushed up by the dealer with his local power and money.

Now can any one tell if such a thing is possible i.e. fool the sensor that air bag system is ok, with out bags being installed?

vikram_d · 9th April 2009, 16:29

Quote:

Originally Posted by visu03

Now can any one tell if such a thing is possible i.e. fool the sensor that air bag system is ok, with out bags being installed?

It is possible. You just have short out the two wires coming out of the airbag sensor and it will think that the airbags are present.

Note: If you try this on a "LIVE" airbag then you stand the risk of blowing it up.

anupmathur · 9th April 2009, 17:05

Quote:

Originally Posted by visu03

The dealer repaired the whole thing and in the process hasn't replaced air bags. Instead he "adjusted" the wiring so that the sensor thinks that the air bag system is working fine. Next time the car meets with an accident air bags do not deploy. Luckly the owner survived and insurance team found that the airbags were not replaced after the first accident. The whole thing is hushed up by the dealer with his local power and money.

Hey, do you happen to know which car and dealer?

MUST name them in such cases!

bblost · 9th April 2009, 17:20

Found some interesting information
Airbag Service Resource | Airbag Replacement FAQ ? Airbag Solutions

Rehaan · 9th April 2009, 18:11

Quote:

Originally Posted by drjones

....refill the gas cartrige...

Quote:

Originally Posted by vikram_d

....The gas cartridge in an airbag is a one time use only device. ...

Correct me if im wrong, but i dont know of any airbags that use a "gas cartridge".

Its actually a chemical reaction (explosion) thats probably triggered by an electrical charge.

cya
R

A bit OT :

YouTube - Air bag explosion

visu03 · 9th April 2009, 18:59

Quote:

Originally Posted by Ardy

A little off topic, but do you know what car was involved in the minor accident? I had heard that Elantra when introduced had a lot of cases airbags being deployed on minor impact.

The vehicle is Pajero.

As i said earlier, this is told to me by a person whom i haven't taken seriously. I will go back to the person who told me this to confirm all the details before i post other details. (Don't want to spread any rumors)

anupmathur · 9th April 2009, 19:27

Quote:

Originally Posted by Rehaan

Correct me if im wrong, but i dont know of any airbags that use a "gas cartridge".

Its actually a chemical reaction (explosion) thats probably triggered by an electrical charge.

It is a gas cartridge. Carbon Dioxide.

laluks · 10th April 2009, 12:23

Quote:

Originally Posted by anupmathur

It is a gas cartridge. Carbon Dioxide.

Can we all have the source to this information. If it is CO2, then God help you.

Quote:

Originally Posted by Rehaan

Correct me if im wrong, but i dont know of any airbags that use a "gas cartridge".

Its actually a chemical reaction (explosion) thats probably triggered by an electrical charge.

You are right about the chemical reaction, but not by electrical charge, but be using high current to heat a resistance, and use heat as the catalyst.

ImmortalZ · 10th April 2009, 12:48

Umm, no, it isn't CO2. In chemical reaction based airbags, it is primarily N2. There exists compressed N2/Argon based technologies also. Propellants are complex and involve multiple stages of reactions to make sure no COx or NOx is generated. Ignition is by an electric match (conductor wrapped with some sort of fast burning material) which in turn activates the propellant which generates the gas that fills the airbag. The whole process of deployment and inflation is over in 0.05 seconds (compared to the blink of an eye - 0.2 seconds).

anupmathur · 10th April 2009, 12:51

Quote:

Originally Posted by laluks

Can we all have the source to this information. If it is CO2, then God help you.

Sorry, there! That would be Nitrogen or other inert gases, but not carbon dioxide!

Moditech Rescue Solutions BV

Seems, after a google, that most modern cars are using a chemical mix to 'explode' and produce Nitrogen.

Also: Servicing - Airbags

GTO · 10th April 2009, 20:12

Standard airbag installations are usually good for atleast 10 years from leaving the factory. Of course, it isn't idiot proof and someone determined could mess around with the sensors. As long as your choice of service center is trust worthy, you have nothing to worry about.

vikram_d · 10th April 2009, 22:47

One more thing i just remembered. On the Swift when the Tech2 scanner is connected there is a function to Airbag diagnostics. This will tell you whether everything is OK or not. I am sure there must be something similar for all cars equipped with airbags.

Edit: I see that you drive an SX4. I am sure the scanner for the SX4 will have a similar function. But not every service centre has a scanner for the SX4 yet. Sadly the Tech2 does not work with the SX4. There is a different scanner for it.

SS-Traveller · 10th April 2009, 23:08

Quote:

Originally Posted by anupmathur

It is a gas cartridge. Carbon Dioxide.

Quote:

Originally Posted by Rehaan

Its actually a chemical reaction (explosion) thats probably triggered by an electrical charge.

It's actually a chemical reaction.

Air bags are actually inflated by the equivalent of a solid rocket booster. Sodium azide (NaN3) and potassium nitrate (KNO3) react very quickly to produce a large pulse of hot nitrogen gas. This gas inflates the bag, which literally bursts out of the steering wheel or dashboard as it expands. About a second later, the bag is already deflating (it has holes in it) in order to get out of your way.

HowStuffWorks "Airbag Inflation"

Found some more relevant material about airbag checks. Please take a look:
Howstuffworks

9th April 2009, 14:02	#1
drjones BHPian Join Date: Dec 2007 Location: Kanchipuram Posts: 176 Thanked: 70 Times	Life & reliability of Airbags? Hi, I would like to know whether there is any method to check the airbag condition and whether we need to kind of refill the gas cartrige at times. I know the " Go crash your car " method of checking guys, I wanna know something without the crash part. Dr.jones
	(1) Thanks

9th April 2009, 14:54	#2
vikram_d Senior - BHPian Join Date: Jul 2006 Location: Bangalore Posts: 2,422 Thanked: 1,188 Times	The only test that can tell you whether the airbag is working fine is the "Blowing It Up" test. The gas cartridge in an airbag is a one time use only device. It cannot be refilled. Also the airbag itself once deployed cannot be re-used.
	() Thanks

9th April 2009, 16:08	#3
visu03 BHPian Join Date: Nov 2006 Location: hyderabad Posts: 131 Thanked: 4 Times	Even I am keen to know how to check if the airbags in the car are working fine apart from blowing them up. I know about the light in the dash, but I think there must be other ways. Here's the back ground for my interest on the topic I heard (may be a rumor) that once a car was sent to the dealer after a minor accident where the airbags got deployed. The dealer repaired the whole thing and in the process hasn't replaced air bags. Instead he "adjusted" the wiring so that the sensor thinks that the air bag system is working fine. Next time the car meets with an accident air bags do not deploy. Luckly the owner survived and insurance team found that the airbags were not replaced after the first accident. The whole thing is hushed up by the dealer with his local power and money. Now can any one tell if such a thing is possible i.e. fool the sensor that air bag system is ok, with out bags being installed? Last edited by visu03 : 9th April 2009 at 16:09.
	() Thanks

9th April 2009, 17:20	#6
bblost Team-BHP Support Join Date: Jul 2007 Location: Hyderabad Posts: 11,284 Thanked: 17,938 Times View My Garage	Found some interesting information Airbag Service Resource \| Airbag Replacement FAQ ? Airbag Solutions
	() Thanks

10th April 2009, 12:48	#11
ImmortalZ Senior - BHPian Join Date: Jan 2008 Location: Trivandrum Posts: 2,195 Thanked: 601 Times View My Garage	Umm, no, it isn't CO2. In chemical reaction based airbags, it is primarily N2. There exists compressed N2/Argon based technologies also. Propellants are complex and involve multiple stages of reactions to make sure no COx or NOx is generated. Ignition is by an electric match (conductor wrapped with some sort of fast burning material) which in turn activates the propellant which generates the gas that fills the airbag. The whole process of deployment and inflation is over in 0.05 seconds (compared to the blink of an eye - 0.2 seconds). Last edited by ImmortalZ : 10th April 2009 at 12:50.
	() Thanks

10th April 2009, 20:12	#13
GTO Team-BHP Support Join Date: Feb 2004 Location: Bombay Posts: 71,815 Thanked: 321,355 Times View My Garage	Standard airbag installations are usually good for atleast 10 years from leaving the factory. Of course, it isn't idiot proof and someone determined could mess around with the sensors. As long as your choice of service center is trust worthy, you have nothing to worry about.
	() Thanks

10th April 2009, 22:47	#14
vikram_d Senior - BHPian Join Date: Jul 2006 Location: Bangalore Posts: 2,422 Thanked: 1,188 Times	One more thing i just remembered. On the Swift when the Tech2 scanner is connected there is a function to Airbag diagnostics. This will tell you whether everything is OK or not. I am sure there must be something similar for all cars equipped with airbags. Edit: I see that you drive an SX4. I am sure the scanner for the SX4 will have a similar function. But not every service centre has a scanner for the SX4 yet. Sadly the Tech2 does not work with the SX4. There is a different scanner for it. Last edited by vikram_d : 10th April 2009 at 22:49.
	() Thanks