Front airbag deployment

[dave_s]

Do both driver and passenger front airbags get triggered at the same time when the computer detects a meaningful frontal impact event? If not what is the correct deployment sequence?

[deggers316]

yes both at same time.
deployment of the airbag takes approximately 30-55 milliseconds

[wildwood]

Just to be different, I thought they went off independently in most cars.

[ChuckFickens]

Some cars have sensors in the passenger seat and won't deploy the passenger air bag unless there is a passenger sitting there to protect.

(would you still respect the car in the morning if it was a meaningless impact?)

[ojread2]

our car's passenger air bag wouldn't go off unless some one was sitting in the passenger seat

[chas2008]

the passenger one on many vehicles can be disabled in case a child/baby seat is on it.
Its not just the airbags that are triggered, the seat belts have pretensioners which also activate to hold the driver/passenger in place. You would also be surprised at the different manufacturers criteria for airbags to be deployed, we see quite hard frontal impacts on Fords/Vauxhalls/Toyotas/where have not deployed,then a slight bump on the front bumper of a 3 series BMW sets the lot off !!! total cost approx £8,000 ..we have actually repaired the same BMW twice within a month due to this...

[ChuckFickens]

"a slight bump on the front bumper of a 3 series BMW sets the lot off !!! total cost approx £8,000"

That's reassuring... Not!

[The Builder]

............... one thing about airbags........... they've certainly stopped people smoking in cars ;o)

[chas2008]

yep, £8,000+ approx £900 labour, rest in parts..Its not just the airbags, the dash,steering wheel gets wrecked,it can also crack the screen, ALL seat belts (front & rear)have to be replaced as per BMW methods, ECUs, battery loom etc etc..there was hardly a mark on the bumper...Almost tempted to kick one (as long as the enging is running) to see what happens !!!
We have also had BMWs that have just clipped a kerb with the rear wheel and all the side air bags have gone off !!!

[ChuckFickens]

Well don't kick mine, please..

[tonyav]

Haven't heard about this prob with BMW, interesting. Is it any particular model ?.

[ChuckFickens]

I'd be interested to (apologies to Dave for a bit of a thread take-over).... I have an E46 and don't really want my air bags going off willy or indeed nilly..

[jno]

not surprisingly - it can cost £2000 to install a new nilly, and as for ...

[chas2008]

not really a problem just the way they are built, it was 60plate 3 series with impact centre of the front bumper, which could of been repaired at a push but we replaced seeing the age of the vehicle. Just waiting for the guy to do it a 3rd time, we need the work..
Its not just BMWs, we had a spate of Clios which had clipped a kerb,always n/side for some reason ,this deployed the passenger seat airbag destroying the seat trim from what i remember was part leather & not cheap, again no body damage.

[tonyav]

Thanks chas.

[chas2008]

the thought of all those airbags going with little more than a car park dink is worrying, must have c**pped himself...

[chas2008]

memory bank is kicking in now... also remember a SAAB going over a speed hump and all the airbags going off...

[craft1948]

When my elderly neighbour managed to reverse at some speed into his neighbours front porch I was amazed his airbag didn't deploy at all.............

[chas2008]

air bags dont deploy from a rear impact..the sensor is behind the front panel or bumper..there are no sensors at the rear of the vehicle.
But like i said i have seen some really bad frontal damaged cars where they havnt gone off..

[Clanad]

A recent informative article here in the western U.S. suggested the old "10 and 2" position for ones hands when driving are unsafe and should be supplanted by a "9 and 3" or use of the "thumb hangers" on the steering wheel and used a documented case of a Highway Patrol officer that knocked out his own teeth by driving with one hand in the 2:00 o'clock position when he struck a deer on the highway causing the airbag to deploy. It deployed so forcefully that his right hand was propelled into his face thereby making him the first known individual to knock out teeth with his own hand...

[jno]

they breed'em tough in the Highway Patrol!