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Old 23rd September 2015, 15:00   #91
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Default Re: Mitsubishi Pajero Sport (Auto) accident - ABS fails to work, airbags not deployed

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Originally Posted by ecenandu View Post
Hey Adit, sad to hear about the accident. Glad that all passengers are safe.

What speed were you doing, Adit, before the accident. Was the road damp?
Did you try to steer the vehicle while applying the brake?
We were at around 90-100kmph; The road wasn't damp; Yes, i did marginally steered the vehicle, but expected it to stop and not skid.
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Old 23rd September 2015, 15:15   #92
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Default Re: Mitsubishi Pajero Sport (Auto) accident - ABS fails to work, airbags not deployed

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Originally Posted by Adit View Post
We were at around 90-100kmph; The road wasn't damp; Yes, i did marginally steered the vehicle, but expected it to stop and not skid.
Oh, okay.
Quote:
Due to this slide, it was virtually impossible to control the car. There was a complete failure of the ABS (Anti-lock braking system)
Few more questions
-The dog jumps from the divider to the road?
-Which lane where you travelling?
-In which direction did you steer during braking?
-By slide, you mean the rear stepping out(over steer- scenario)?
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Old 23rd September 2015, 16:15   #93
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Default Re: Frontal Crash - Airbags didn't deploy. Why?

Adit- Let's thank god that no serious injuries followed as a result of the shunt. My prayers and best wishes to your family for putting this behind and moving ahead.

I'm going to entirely skip over the how's and the why's and the when's. This is a purely technical post.

The Pajero Sport comes with a separate SRS-ECU that controls the airbags. This SRS-ECU according to the Workshop Manual is readable even after a crash for "post-collision diagnosis". So firstly regardless of what Mitsubishi does, ask them to supply you with the SRS-ECU Check Report.

Secondly, as for the non-deployment of the air-bag-the sensor sits slightly high up just ahead of the front wheel well [See Pg. 52B-22]. From the pictures you have attached its evident that there was absolutely no intrusion into the engine bay area where the sensors sit, which is probably the reason as to why the airbag's were not triggered.

Thirdly, the divider on the highway does not appear to be very high and your impact with the divider seems to have been absorbed by the tyre which has exploded/burst (I concede the benefit of doubt that the tires might have failed due to the tremendous yaw induced after the spin).

In fact on another thread our fellow bhpian Kischarit was left rather bewildered when a low speed impact triggered his airbag's (Maruti Suzuki Ertiga ZDi: Things get really LUVly). In his case it was probably because the sensor got hit from the underside of the body.

I'm attaching the workshop manual for the SRS System (its probably applicable since the mechanicals of the Challenger/Triton/Montero Sport [of which this manual is] are identical to our Pajero Sport).

I hope this helps!
Attached Files
File Type: pdf supplemental-restraint-system-srs.pdf (724.9 KB, 220 views)
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Old 23rd September 2015, 18:27   #94
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Quote:
Originally Posted by Adit View Post
Hi,

I must have missed to mention that, I had a head on collision with the DIVIDER as the car skid and that is the time when I expected the Airbags to deploy.

Thanks.
Thank God that everyone is safe without major injuries.

Even if the airbags were not deployed during the hit against the divider, they should have deployed when the car turned turtle.

Make sure u thank God that you are safe and also for the fact that the structure held up well during the accident. Imagine if you were in a car with poor structural rigidity.

So Mitsubishi hasn't compromised on structural rigidity which is a good takeaway here.
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Old 23rd September 2015, 19:50   #95
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Default Re: Frontal Crash - Airbags didn't deploy. Why?

Quote:
Originally Posted by shady_lawyer View Post

The Pajero Sport comes with a separate SRS-ECU that controls the airbags. This SRS-ECU according to the Workshop Manual is readable even after a crash for "post-collision diagnosis". So firstly regardless of what Mitsubishi does, ask them to supply you with the SRS-ECU Check Report.
Hi,

According to Mitsubishi the SRS / ABS report shows normal working condition; The brake oil levels were fine.
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Old 23rd September 2015, 21:10   #96
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Default Re: Frontal Crash - Airbags didn't deploy. Why?

Not quoting anyone on this thread, as many seem to be of the same opinion. The airbag sensors do not have to be directly impacted for the airbags to deploy. The airbag sensors work with a "ball in tube" setup and deployment primarily depends on rate of deceleration.

What this means is - if the vehicle comes to an abrupt stop, which is way less than the normal stopping time for a given speed, even lesser than a panic braking situation, then the airbags would deploy. The sensor need not necessarily be directly impacted.
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Old 23rd September 2015, 21:44   #97
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Default Re: Frontal Crash - Airbags didn't deploy. Why?

Just be grateful that no one's seriously hurt. But this misconception has to stop in forums. Airbags don't deploy in all accidents.

Front airbags(which are the only ones in your Pajero) deploy only on direct frontal impact, when your crumple zone deforms to a large extent. From the pictures, it's evident that your cross member is intact and damage to the engine bay is minimum. The airbag sensors are generally above the front suspension. So, I'm actually not surprised that Airbags didn't deploy. Sorry for being harsh, but that's the truth.

But ABS not working is a matter of serious concern.
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Old 24th September 2015, 12:54   #98
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Angry Re: Frontal Crash - Airbags didn't deploy. Why?

Thanks for all your views on ABS / Airbags and insight to a lot of technical stuff which I was not aware of.

My blog on this incident (similar to what I have already mentioned here)
https://www.tumblr.com/blog/neverwillieverbuyapajero

The point is that when you buy a car for 31L, you expect something to work on D-DAY. Specially, when you were told / explained each and every safety feature of the vehicle, while completing the SALE.

I may be a normal customer with limited knowledge and Mitsubishi mis-represented the facts. That's all I want to say...
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Old 24th September 2015, 15:27   #99
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Default Re: Frontal Crash - Airbags didn't deploy. Why?

Here are few pages from Hyundai Creta's owners manual, explaining situations when the airbags may not deploy.

Frontal Crash - Airbags didn't deploy. Why?-screen-shot-20150924-11.48.43-am.png

Frontal Crash - Airbags didn't deploy. Why?-screen-shot-20150924-11.48.57-am.png

Frontal Crash - Airbags didn't deploy. Why?-screen-shot-20150924-11.49.14-am.png

And, one should always remember that all these safety features have limitations as well.
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Old 24th September 2015, 15:50   #100
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Default Re: Frontal Crash - Airbags didn't deploy. Why?

would be interesting to know in which scenarios none of the 6 airbags deploy.
Adit, any response from mitsubishi on ABS not triggering.
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Old 24th September 2015, 16:07   #101
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Default Re: Frontal Crash - Airbags didn't deploy. Why?

Another reason of airbags not deploying - A pending Recall.
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Old 24th September 2015, 16:07   #102
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Default Re: Frontal Crash - Airbags didn't deploy. Why?

Quote:
Originally Posted by Adit View Post

I may be a normal customer with limited knowledge and Mitsubishi mis-represented the facts. That's all I want to say...
I am glad to hear that you and your family are safe by the grace of God. I wouldn't necessarily think that Mitsubishi misrepresented the facts.

Airbag is a passive deterrent and much has been said and explained in various threads on the forum on how, why and when airbags do not always get deployed. Looking at the condition of your vehicle, I will put my money on ABS not deploying.

ABS, too can exacerbate the severity of a situation in certain conditions (it especially increases the chances of a rollover). One such condition is when ABS comes to play while the driver is veering the steering. Though you may not have realized or recollect now, but there is a distinct possibility that you did exactly that while avoiding the animal.

On the other hand, you should congratulate yourself for sticking to safety rules by ensuring everyone was belted (even now majority don't) and your car too, for its apparent structural strength.
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Old 27th September 2015, 00:58   #103
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Default Re: Frontal Crash - Airbags didn't deploy. Why?

Quote:
Originally Posted by Adit View Post
Thanks for all your views on ABS / Airbags and insight to a lot of technical stuff which I was not aware of.

The point is that when you buy a car for 31L, you expect something to work on D-DAY. Specially, when you were told / explained each and every safety feature of the vehicle, while completing the SALE.
Hey Adit, first of all great to know that you and your family is safe.

Regarding the issue of Airbags and ABS, I think its been explained well as to possibly why the airbags did not deploy (btw I have experience of airbags deploying upon hitting a dig on a highway), but ABS not working certainly is a good question.

Lets assume for a second that there was no fault with ABS, its one of the most basic safety features and likelyhood of it going bad is very low unless you had the warning light on. Keeping above assumption in mind what could possibly have happened is that since you were at reasonably high speed and braked hard + changed direction a bit trying to avoid the dog, the momentum of the car would have caused lot of sideway pressure on the tyres and given that Pajero being a heavy SUV with higher center of gravity the tyre grip was not enough and you lost traction. It would be ESP that would come in handy in situation like this because your are skidding not in the direction of your steering and ABS cant do much.

Doesnt matter what safety features a car has, they are designed to work only under certain scenarios but a real accident can lead to limitless possibilties that designers would not have covered. End of the day a good body structure and seat belts are the most important aspects of safety, rest is all secondary (SRS) and you should be glad that you had that covered.

Last edited by supertinu : 27th September 2015 at 01:00.
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Old 9th February 2016, 23:06   #104
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Default Re: Frontal Crash - Airbags didn't deploy. Why?

Quote:
Originally Posted by Ragavsr View Post

Even if the airbags were not deployed during the hit against the divider, they should have deployed when the car turned turtle.
Front airbags do not deploy in rollover collisons. There would offer no protection in a rollover. You need side and curtain airbags in such situations.
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Old 28th February 2016, 17:14   #105
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Default Re: Frontal Crash - Airbags didn't deploy. Why?

Moderators please move this reply to appropriate thread if it doesn't fit here.

I happened to visit VW Mysore for my annual service and came across a curious case of airbag deployment. I saw a perfectly fine new Vento from the side near the body shop area but only to notice that the airbags was deployed. I assumed that the engineers might be testing out something and approached the vehicle just out of curiosity. When I had a talk with the mechanic, he said its accident vehicle and hence it was deployed.

Upon seeing the front bumper, I was shocked to say the least. The bumper was in intact with minor cracks in the front

Have a look the pictures which I took (sorry for the clarity). It looks more like a faulty airbag sensor than anything else to me. As per mechanic, the owner apparently is going for insurance claim and was so irritated that he went to extent of saying that he does not need airbags if its soo sensitive. Shouldn't this be covered under warranty for faulty sensor than blindly claiming insurance. Shouldn't VW be looking at this more seriously since such low speed impact can happen to anyone in bumper to bumper traffic
Attached Thumbnails
Frontal Crash - Airbags didn't deploy. Why?-img_20160227_093913906_hdr.jpg  

Frontal Crash - Airbags didn't deploy. Why?-img_20160227_093920477.jpg  

Frontal Crash - Airbags didn't deploy. Why?-img_20160227_093932056.jpg  

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