SRS Airbag inflation?

[butane8 Avid PP Poster! Find all posts View Profile Close butane8]

After reading the threads regarding sliders and side airbags, its got me curious if anyone has had side or front air bags
accidently inflate due to offoad knocks etc. how much of a impact will set 'em off?

have noticed the crush distance for the front sensors, but the side has got me thinking,

[Prado04 Junior Member Find all posts View Profile Close Prado04]

Re: Airbag inflation?

Air bags use 2 things to set them off one is the speed and the other is a accelerometer. Most air bags now days will not go off if u are under 40km/h so the chances of setting them of while off road would almost impossible to do.

[MickL Addicted PP Member Find all posts View Profile Close MickL]

Re: Airbag inflation?

have noticed the crush distance for the front sensors, but the side has got me thinking,

They are not "Crush" sensors but rather "Deceleration" sensors. To activate you need one sensor (Front/side) and the safing sensor (centre console) to activate. The system is based on the forces generated by deceleration not a physical crush/crumple/contact.

The forces required are large, far exceeding what you'll generate rock or dune hopping... if you go from 40 or 50kmph to zero instantly then believe me you want the SRS to go off and your Prado will need a little work anyway :wink:

Mick

[butane8 Avid PP Poster! Find all posts View Profile Close butane8]

Re: SRS Airbag inflation?

so what is all the fuss about airbag compatible bullbars and sliders, if its the deceleration that attivates 'em not the impact. spose their crumble zones are affected?

[MickL Addicted PP Member Find all posts View Profile Close MickL]

Re: SRS Airbag inflation?

spose their crumble zones are affected?

That right. Vehicles a designed to crumple to absorb as much of the force of and accident as is possible. The SRS system works within that crush rate to set of air bags at just the right moment. To early and it'll already be deflating as your head hits it, to late and your head would still hit the wheel first, then get a double wammy as the bag hits you.

Any accessories that will effect the crush rate has the potential to not only increase the minimum impact required to deploy airbags but potentially throw the timing of the deployment out and reduce it's effectiveness.

It all comes down to milliseconds and is really a fantastic piece of engineering... look at the side airbags; Your head is about 12 inches from the side and in an accident the systems reacts so fast and just at the right moment to infate the bag and reach full or near full inflation just as your head comes in contact with it.

Mick

[Donk Junior Member Find all posts View Profile Close Donk]

Re: SRS Airbag inflation?

When airbags are removed from vehicles under warranty (if for instance a horn pad is marked or similar) we have to activate them before they are placed in the warranty storage room & it is amazing thing to watch as when you let them off (Toyota have a procedure & a special service tool for doing this with the bag removed from the vehicle) as there is just a loud bang & a deflated bag

Each time this has happened i have never seen a bag inflate as it happens so quickly

Regards Don