Question about seatbelt sensors and airbags

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DiogoBrand
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Question about seatbelt sensors and airbags

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So I drive a 2012 GM Cruze, and it has that feature where if you don't wear your seatbelt it makes an annoying sound for a minute. Even though I'm used to wearing my seatbelt when I go onto the highway or if I drive on a bigger city, it can get really annoying sometimes, because my parents live in such a small town (7000 people or so) that usually wearing and taking off the seatbelt takes longer than the trip itself.

A few years ago I had unplugged a connector under each of the front seats, and that got rid of the sound, but it got me worried about the effects it might have on the airbag system in case of an accident. So if someone could clarify a few questions I have it would be greatly appreciated.

- Is it true that the airbag can be dangerous if it goes off without the passenger wearing the seatbelt?
- Is it true that car uses weight sensors on the seats to control the strenght of the explosion?
- If I unplug those connectors, could it cause the airbag to not go off or go off in a wrong manner (too strong/too weak)?

Anything else you guys want to add to the conversation about what I can and cannot do without compromising the safety of the vehicle would be nice as well.

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Pyrone89
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Re: Question about seatbelt sensors and airbags

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DiogoBrand wrote:
Mon Aug 05, 2019 11:25 pm
So I drive a 2012 GM Cruze, and it has that feature where if you don't wear your seatbelt it makes an annoying sound for a minute. Even though I'm used to wearing my seatbelt when I go onto the highway or if I drive on a bigger city, it can get really annoying sometimes, because my parents live in such a small town (7000 people or so) that usually wearing and taking off the seatbelt takes longer than the trip itself.

A few years ago I had unplugged a connector under each of the front seats, and that got rid of the sound, but it got me worried about the effects it might have on the airbag system in case of an accident. So if someone could clarify a few questions I have it would be greatly appreciated.

- Is it true that the airbag can be dangerous if it goes off without the passenger wearing the seatbelt?
- Is it true that car uses weight sensors on the seats to control the strenght of the explosion?
- If I unplug those connectors, could it cause the airbag to not go off or go off in a wrong manner (too strong/too weak)?

Anything else you guys want to add to the conversation about what I can and cannot do without compromising the safety of the vehicle would be nice as well.
Dont know how your country works, but I suggest not to meddle with the saftey systems. They are designed in a specific way for a reason. And you could face insurance repercussions, police fines, vehicle inspection fines and lawsuits if anythimg happens to a passenger not to mention your own safety. Is it really that big of a burden to do a 2 second job? Do it while starting the engine with your other arm like I do.

Greg Locock
Greg Locock
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Re: Question about seatbelt sensors and airbags

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1) yes. if you aren't wearing a seat belt you will be much further forward in a crash, and moving with greater velocity. The airbag will strike you with greater force. Some cars actually use the seatbelt sensor and depower the airbag if you aren't wearing a seat belt.In a correct deployment the bag is fully inflated when you strike it.
2) Some cars do, some don't. I think it is now compulsory in the USA. Your handbook should tell you whether small passengers are allowed in the front seat, if they are then it has a weight sensor coupled to the airbag.
3) yes

Fun fact, the bag is inflating at roughly 300 km/h until quite late in the process. That's quite a punch in the face.

Jolle
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Re: Question about seatbelt sensors and airbags

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I remember that USA cars had bigger airbags because lots of Americans didn’t use the seatbelt, making it quite bigger bang. Now the Cruze, is that one of the deawoo cars? Then it might be a small one.

But really? No seatbelt? One quick move and you’re bucketed in. Especially in small towns, where the majority of accidents happen where you need a seatbelt.

Must be some darwinism going on in the old colonies

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izzy
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Re: Question about seatbelt sensors and airbags

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DiogoBrand wrote:
Mon Aug 05, 2019 11:25 pm
So I drive a 2012 GM Cruze, and it has that feature where if you don't wear your seatbelt it makes an annoying sound for a minute. Even though I'm used to wearing my seatbelt when I go onto the highway or if I drive on a bigger city, it can get really annoying sometimes, because my parents live in such a small town (7000 people or so) that usually wearing and taking off the seatbelt takes longer than the trip itself.

A few years ago I had unplugged a connector under each of the front seats, and that got rid of the sound, but it got me worried about the effects it might have on the airbag system in case of an accident. So if someone could clarify a few questions I have it would be greatly appreciated.

- Is it true that the airbag can be dangerous if it goes off without the passenger wearing the seatbelt?
- Is it true that car uses weight sensors on the seats to control the strenght of the explosion?
- If I unplug those connectors, could it cause the airbag to not go off or go off in a wrong manner (too strong/too weak)?

Anything else you guys want to add to the conversation about what I can and cannot do without compromising the safety of the vehicle would be nice as well.
My grandfather used to be an accident investigator. If you're too close to the airbag when it goes off it can kill you. Personally I can't drive a car anywhere without the seatbelt on and locked, after he told me about coupling: you are going to end up doing the same speed as the post-impact car, so the longer it takes for the belt to start slowing you down the faster you will decelerate once you do start.

You want the seat belt to couple you to the car so that it starts slowing you down as soon as possible. The later you start slowing down the more work you're asking the airbag to do and the more risk there is of contacting it while it's still inflating which will give your head a huge G.

Also a small town impact can easily be 30mph or more and if you watch some crash tests you'll see that is pretty big! And if you have a head-on with a heavier vehicle you can end up going backwards giving you actually a 40mph crash or whatever. Also there are rollovers where with no belt you can be thrown out and have the car on top of you.

And finally the airbags assume a trajectory where your hips stay in the seat while your head arcs forward and down. And finally finally in an offset frontal you might go at an angle and pretty much miss the airbag.

So please always wear your belt. It takes me 3s. Do it up tight, not over a coat, and flip the belt at your shoulder to lock it. And sit as far back from the wheel as you comfortably can. An airbag is wonderful, but only if it's finished inflating by the time you hit it. While it's inflating it's basically a bomb in a cover.

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strad
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Re: Question about seatbelt sensors and airbags

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Agree with Pyrone about insurance. Especially since Chevy has a recorder that tells about belts and speed and acceleration and braking in the minute or so before an incident. Big Brother is watching you. They have a black box.
- Is it true that the airbag can be dangerous if it goes off without the passenger wearing the seatbelt?
YES! It can kill you.
- Is it true that car uses weight sensors on the seats to control the strength of the explosion?
While many do have weight sensors I'm pretty sure it controls whether they go off or not.
- If I unplug those connectors, could it cause the airbag to not go off or go off in a wrong manner (too strong/too weak)?
For any number of reasons it is not a good idea to mess with the circuitry of any safety device.
To achieve anything, you must be prepared to dabble on the boundary of disaster.”
Sir Stirling Moss

Titchener
Titchener
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Re: Question about seatbelt sensors and airbags

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I've seen a crash with minimal damage but the driver died instantly, they weren't wearing a seat belt and the air bag broke their neck in what was a perfectly survivable crash.

If you've altered the airbag system in anyway I'd be astonished if no warning light showed on the dashboard.

As far as I know, the only alteration to airbag activation comes from the point of impact so the car knows if it only needs to deply front or side etc..

Just wear the seat belt.

AJI
AJI
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Re: Question about seatbelt sensors and airbags

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Wasn't the airbag primarily invented for those who didn't wear a seatbelt, and as a secondary safety system for those who do? US 'non-seatbelt' airbags can kill children who are sitting in the front seat because they're head is exactly where the airbag deploys if they are sitting forward on the seat, but an adult... I don't think so? Kind of negates the point of having an airbag..?
I believe the first case of a serious accident where airbags deployed in both cars and both drivers were fine, neither were wearing a seatbelt.

Anyway, I'm a bit off topic. Diogo, not that I'm condoning this (a single human life is more sacred than the planet etc..), but you can usually code the car to think it's in a country where they don't care about seatbelt chimes. Do the door and key chimes and daytime running lights at the same time, I did!

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strad
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Re: Question about seatbelt sensors and airbags

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In order to do its job, an airbag must fully inflate within a split second. That is why they use an explosive chemical for their inflation. Its inflation has been described as sounding like a gunshot. If one’s face gets in the way during the airbag’s deployment, the bag will hit their face with the force of a baseball bat.
If one is not seat belted, hard braking can bring their face within striking distance of the airbag which then inflates during the car’s collision. Airbags can break bones and cause serious or even fatal injuries to the head, neck, and chest during its deployment. Your face is only supposed to contact the airbag after it has fully deployed. Wearing your seat belt ensures this.According to the University of Pittsburgh Medical Center, drivers and front-seat passengers have a higher chance of sustaining a spinal fracture and spinal cord injury when airbags are used without seat belts during a frontal collision
To achieve anything, you must be prepared to dabble on the boundary of disaster.”
Sir Stirling Moss

AJI
AJI
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Re: Question about seatbelt sensors and airbags

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strad wrote:
Tue Aug 06, 2019 8:18 pm
...According to the University of Pittsburgh Medical Center...
Got a link to that strad?

In the meantime, enjoy an ancient video of the first airbag equipped productuon car. Lap sash seat belt recommended to give you that frontal lobe massage you've been looking for.

https://youtu.be/ZyYdUQl1WNc

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strad
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Re: Question about seatbelt sensors and airbags

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All it takes is a quick Google search there are other links but this is where I got that quote
https://www.mikelewisattorneys.com/why- ... dangerous/
I'm not prone to make stuff up.
To achieve anything, you must be prepared to dabble on the boundary of disaster.”
Sir Stirling Moss

AJI
AJI
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Re: Question about seatbelt sensors and airbags

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strad wrote:
Tue Aug 06, 2019 11:21 pm
All it takes is a quick Google search there are other links but this is where I got that quote
https://www.mikelewisattorneys.com/why- ... dangerous/
I'm not prone to make stuff up.
The university paper strad... I know you haven't read it

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strad
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Re: Question about seatbelt sensors and airbags

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So Mike Lewis atty. is lying?
How about this article from 2013?
Airbags are designed to work together with seat belts to save your life. Wear your seat belt.
Airbags have saved thousands of lives and prevented countless injuries since becoming standard in cars and other vehicles. They’re a great invention. However, airbags have earned themselves a bad reputation: though they save lives on the whole, airbags have killed people and continue to do so each year. These deaths are some of the most preventable ones in the world.
The number-one reason that airbags can kill: drivers and front-seat passengers don’t wear their seat belts. Airbags and seat belts are safety tools that should be used correctly together in order to minimize the risk of injury during car crashes. The seat belt is designed to prevent your body from moving forward with the momentum your car had just before the collision. Airbags are meant to cushion your torso and head and prevent contact with the hard interior surfaces of the vehicle. For this reason, they move in the opposite direction that your body does. They inflate extremely quickly, sometimes at 400kph, and even a soft fabric that hits the head or chest at that speed could break bones and cause severe internal injuries.

When an airbag and seat belt work together properly, the seat belt prevents your whole body from flying forward, and the airbag cushions your upper chest so that your chest and head do not hit the steering wheel, dashboard or front of the car.
When you do not wear your seat belt, the two safety devices cannot work together properly; your body moves toward the airbag at high speeds, and the airbag moves toward your body at even higher speeds. During this collision, airbags can kill you.are they all lies?
Does it not just make sense to you?
How many do you want me to post?
Airbags first began appearing in vehicles in 1991. According to the Chicago Tribune, these devices have been responsible for saving more than 1,800 lives since that time. Conversely, the Tribune reported that only 62 deaths can be attributed to airbags, and the majority of the individuals killed in these cases were not properly restrained with seat belts.
To achieve anything, you must be prepared to dabble on the boundary of disaster.”
Sir Stirling Moss

AJI
AJI
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Re: Question about seatbelt sensors and airbags

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strad, my point (which I poorly made in the first post) was that airbags first installed in the early 70's were being explored as a non-intrusive safety system mainly because there was no law to wear seat belts in the US. Sure, even in the video I provide they say wear a lap belt, but they don’t say it’s a must and they specifically say you don’t need a shoulder belt.
Yes, I concede that there could have been cases of death by airbag, but where's the actual data? Are the majority of the deaths in the US, where high power airbags are installed because seat belt use is not compulsory? Are the majority of deaths children, before there was proper education about sitting in the front seat? Are we just going to throw anecdotal evidence at each other and see what sticks?

Here’s an update on my first post for your reading pleasure. I finally found the article.
While I wrongly stated that neither were wearing a seatbelt, one person in-fact was. The best bit though (something that I had forgotten), they were both driving the exact same car! Note the quote from ‘Woody’ at the end. This was the general thinking at the time when airbags were finally re-introduced.
...Ronnie Woody headed west on Route 640 in his brand-new Chrysler LeBaron. Coming in the opposite direction on the two-lane road was Priscilla Van Steelant, also driving a Chrysler LeBaron. According to the police report, Van Steelant, 39, strayed over the unmarked center of the road and smashed into Woody head-on, the two cars colliding at an estimated combined speed of 70 mph. “I saw a car coming down the wrong side of the road,” says Woody, 22, a construction worker. “I thought, ‘Surely she’s going to get out of the way.’ The next thing I remember is some guy asking me if I was all right.”
Amazingly, he was, as was Van Steelant. Woody escaped with a cut on his elbow and a bruised knee, while Van Steelant had a bloody nose and various minor bruises. Paramedics who arrived expecting a difficult rescue found it hard to believe that both drivers had walked away from a potentially fatal crash. “They said to me, ‘Where’s the driver?’ ” reports Van Steelant. “I said, ‘I am the driver.’ I had to argue with them, to convince them I was the driver.”
Woody and Van Steelant owe their miraculous escape to air bags that inflated in½5th of a second. This was the first head-on crash in which both cars were equipped with the air bags. Consumer groups have long pressured automakers to install air bags in all cars. Chrysler has been a leader, equipping all their domestically produced cars with driver-side air bags. Both Woody, who wasn’t wearing a seat belt, and Van Steelant, who had buckled up, are living proof of air bags’ effectiveness. “You can’t make everybody wear a seat belt, but you can put an air bag in every car,” says Woody.
https://people.com/archive/dueling-air- ... -33-no-16/

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strad
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Re: Question about seatbelt sensors and airbags

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Well that article is from 1990. Quite a lot of water under the bridge since then. But I nor do I think anyone else has said that not wearing a seatbelt and getting hit with the airbag is deadly in all cases. I don't care if it's 1 in a 1000 I don't think most people want that chance.
I have entered many raffles for a Corvette or the like where I had a 1in 1000 chance and never won so yeah your chances are in your favor of just getting a broken nose or jaw but I'd rather not have those outcomes either. It all depends on type of accident, speed, how far you sit from the wheel etc.. Most people I know don't want to take the chance.
To achieve anything, you must be prepared to dabble on the boundary of disaster.”
Sir Stirling Moss