Air Bag Failure

My husband rolled his F250 in the northeast winter storm yesterday. (Broken leg, concussion but ok!!) The air bags didn’t deploy. He hit a tree impacting the front driver’s side, hard. Shouldn’t the air bags have deployed? Neither did. He had the engine replaced about 6 months ago by our mechanic. Would replacing an engine also include having to touch the air bag system? Don’t want to ruin my mechanic’s day. Just want to know why they didn’t deploy and if it was a manufacturer defect, or the result of having had the engine replaced and maybe something not being re-connected.

Thanks for any input. New engine: 5.4ltr Jasper.

If the airbag light was lit up on the dashboard after the engine replacement, then that might be attributable to the mechanic but your husband should have noticed right away. It is very unlikely the engine change was at fault.

You say the truck hit hard on the front left. In what direction? Truck sliding sideways into the tree? That direction of impact would likely not have triggered a steering wheel mounted airbag. You don’t say what year F250 so I can’t even guess whether it has side airbags or not. Side bags would likely deploy in a side impact.

If your husband hit mostly moving forward, then yes, the airbag should have deployed. If that is the case and if you intend to file a lawsuit you must contact a lawyer ASAP so they can secure the truck before evidence is lost.

Glad your husband is OK and sorry about the loss of a truck in which you just replaced the engine.

There are several factors that enter into whether or not an airbag will deploy.

  1. Was the airbag symbol in the instrument cluster lit up before the accident? If it was, the bag WILL NOT pop. I doubt the engine installation had anything to do with it.
  2. How fast was he going at the time of impact?
  3. Was his seat belt fastened?
  4. What year is the truck?

Second generation airbag systems will not pop if the impact speed is low and the belts are buckled. There is no need.

Airbag deployment is based on directional crash force, not just severity. A severe crash with an offset will sometimes generate very high crash forces but not sufficient force in the forward direction to trigger a front airbag. In your husband’s case the truck likely spun as it hit the tree on the one side, blunting the forward crash force and converting it into side forces that do not cause front airbag deployment. You also say he “rolled” the truck. If it rolled after impacting the tree then additional momentum was transferred to the rolling action of the truck, further dissipating the crash force in a non-forward direction.

People often misunderstand how airbags work. I have had to explain to numerous people who were rear-ended that front airbags deploy when you hit something hard (rapid deceleration) not when you are hit from behind (momentary rapid acceleration).

We don’t have enough information to know whether the airbag system functioned properly or not in the accident. Too many unknowns.

Year, make, model? Speed, angle, and direction of impact? Seat belts fastened and fully functional? Have you had the truck since it was new? Even with this info we’re a bunch of people on the internet. I think the crash investigators are the only ones who will be able to determine if the airbags should have deployed.

If in fact (and this is a really big if) there was some trouble with the airbag system that was related to the engine replacement then your husband shouldn’t have been driving around for 6 months with an airbag warning light on.

Other than the missing info requested by others, I’d like to know how fast he was going in a winter storm that caused him to roll the truck…

IF push ever came to shove against the mechanic or FOMOCO they will find out exactly how fast he was going because the electronics won’t divulge anything other than the truth.

Air bags save lives, but when they fail to work properly they can cause severe injuries for people.

The truck should have “black box” info stored somewhere. The info includes the speed of the truck, braking, gas petal position, etc. Such info can help determine if the airbags should have deployed or not. Was the driver wearing a seat belt? If yes and you feel his injuries are worse due to a vehicle safety issue such as airbag failure you need a lawyer for advice. If no, the airbags deployment would have made his injuries far worse.

Quoting @UncleTurbo

“If no, the airbags deployment would have made his injuries far worse”

Why would the airbags have made his injuries worse if the driver were not wearing his seat belt? I doubt there has ever been a case study of airbags that would prove anything but the opposite.

Air bags are a SUPPLEMENTARY RESTRAINT SYSTEM (SRS). The seat and shoulder belt is the primary system. Air bags are not a substitute for seat belts.

When you are not held in place by a seat belt the force of the airbag will throw you back in the seat with such force that you will have head trama or a broken neck. Airbags are designed to work in conjunction with seat belts. Airbags alone do not protect the occupants of the car.

Why would the airbags have made his injuries worse if the driver were not wearing his seat belt? I doubt there has ever been a case study of airbags that would prove anything but the opposite.

As was stated above, airbags with no seat belts are worse than nothing at all. For this reason modern airbag systems are designed NOT to deploy if the seat belt is not buckled.

"...modern airbag systems are designed NOT to deploy if the seat belt is not buckled."

Apparently, this is a myth. Per NHTSA:

It’s not a myth

I’m a professional mechanic, just like @asemaster, and that’s what I learned

@insightful and NHTSA are not enough for me to stop believing this “myth”

"Air bags are not a substitute for seat belts."

They certainly are used that way.

Airbags became mandatory as a “Supplemental Restraint System.” Given that seat belt use was not 100%, the NHTSA wanted something that worked, regardless of the actions of the “nut behind the wheel.” That “something” was either airbags…or those awful self-actuating seat belts. You had to have one or the other!!

"NHTSA are not enough for me to stop believing this "myth" "

Please cite your reference.

As a matter of fact, I’m not citing a reference, because I don’t have one. And frankly, I’m not motivated to find one and cut and paste it. I have neither the inclination, nor the energy

That link that you provided did not 100% say that airbags must deploy in all situations

It merely requested that you contact NHTSA if you’re injured, and the airbag did not deploy

I see it as a matter of . . . NHTSA is collecting information, for their studies, because that’s exactly what they say.

I’m not sure what you’re reading into it

There are MANY parameters and conditions which have to be met, for an airbag and/or ETR to deploy

There seems to exist a myth which says that if you’re hurt and the airbag didn’t deploy, the vehicle’s airbag system is defective, and you might as well contact a lawyer

I consider that jumping the gun, in some cases

Just want to know why they didn't deploy and if it was a manufacturer defect, or the result of having had the engine replaced and maybe something not being re-connected
TRANSLATION: Just want to know if I have a case against "deep pockets" FoMoCo, or against "not so deep pockets" Repair Shop???

I agree with asemaster and db4690; and meanjoe75fan.

Sometimes questions are posed with a subtle (sometimes not so subtle) intent of gaining some “go get 'em” backing.

The truck had a new engine installed 6 months ago. This could be taken to mean the truck is 15 years old and has 300k miles on it as far as I know. Warranty periods do have an end point and I would imagine the warranty expired on this truck a long time ago.

The odds of additional info are not very high IMO but I’d like to know how fast hubby was going when he rolled it in the muck.
The ECM knows this and if a lawsuit surfaces the mechanic and FOMOCO will know it too.

About 7 or 8 years ago the local news did a story on 3 teens injured and 1 killed when the Ford Explorer they were in swerved off the road and hit a tree to avoid a turning left oil tanker. This happened on a county 45 MPH highway during lunchtime from school. Several stories a week on this tragedy and my thought the entire time was “ok, how fast were they going?”

Six months later it was revealed in a followup story that the ECM coughed up the info that they were doing 98 MPH when they left the roadway and 0 when they plowed into a large tree that did not move an inch.
Almost a 100 MPH on a narrow, hilly, tree lined country road with posted 45 signs all down it and suddenly faced with an oil tanker slowed to a crawl in front of them…

Yes, airbags are designed to be SUPPLEMENTAL with the use of seat belts. I still believe that if one is not smart enough to fasten their belt, they will be better off with a working airbag than with nothing to cushion the impact.