Jump seat seat belt failure

[ckessel]

Isn't that a bit Chicken Little, at this point?

No, this is precisely why NHTSA exists. They have to have data in order to understand trends that may not be visible either to individuals or, perhaps more importantly, to manufacturers. NHTSA could, for example, determine that the seat belt 3rd party manufacturer has had issues in other non-Tesla cars as well.

This isn't about punishing Tesla, it's about providing a safety agency with enough data to make good decisions within a much larger context.

 

[alexucf]

No, this is precisely why NHTSA exists. They have to have data in order to understand trends that may not be visible either to individuals or, perhaps more importantly, to manufacturers. NHTSA could, for example, determine that the seat belt 3rd party manufacturer has had issues in other non-Tesla cars as well.

This isn't about punishing Tesla, it's about providing a safety agency with enough data to make good decisions within a much larger context.

Exactly. As a parent who uses the seats every day with two toddlers, PLEASE contact NHTSA. If there's an issue with the seats structurally, it's important to get a third party to review it. That's why they exist.

And if there is a problem, the seats should be recalled immediately. That's not an anti-tesla thing at all. It's a do-whats-right thing. Especially for the car thats considered to be the safest thing on the road.

 

[pmadflyer]

I'll throw my voice into the group recommending a report to the NHTSA. Just because this has been posted about once, doesn't mean it occurred only once. Better to be safe than sorry.

 

[Chris TX]

Eagerly awaiting the recall notice for my 3rd row seat belts

 

[jive_devil]

Is it possible to get a further back pic of what failed? I see the pieces of what appears to be the latching buckle, but I'm not sure. There are several mechanisms that keep the belts in place (anchors at top, bottom, and a midpoint for adjustment). It also might be harder for me to recognize as I have the first generation rear facing seats, and these appear to be 2nd generation (based on the stitching and trim).

Thanks, OP, for putting this up.

 

[Zarwin]

Here is the piece that is the focus of this thread:

 

[EarlyAdopter]

As others have said, hitting the brakes would actually relieve tension from the rear facing seat belts. This adjuster coming apart is probably coincidence.

Actually, it sounds like it might have been very related.

Based on Zarwin's description of how the mechanism works, it sounds like the tension of a tightened belt helps hold things together securely. When the OP stopped fast, the tension would have been relieved on the belt as the rear facing passenger was pushed into the seat back, perhaps allowing the mechanism it to pop apart if the retention spring was misaligned.

 

[trbeals]

I was able to reproduce at least a partial failure of the seat belt adjuster (i.e. got one of the two sides of the retaining wire spring to pop free of the divot on one side of the metal crossbar). To do so, I simulated the tail of the seat belt (the loose end) being trapped under the child's bum, and then applied moderate-firm force to the main part of the seat belt, pulling it towards myself (toward the back of the car) as if the child was leaning forward hard. The combination of this force with the seat belt tail being held trapped caused a torsional force to be exerted on the metal crossbar, which was sufficient to pop the spring free from one side. I heard a small metallic "ping", and on careful inspection it's visible (see red-circled area in photo below), but it would be easy to miss.

With one side of the spring loose, it may become possible for the metal crossbar to twist sufficiently to work loose, although I didn't observe that happening. It's possible that this is what happened in the original poster's situation, and when the sudden braking momentarily released tension, the seat belt adjuster came apart.

I was easily able to fix the seat belt adjuster by removing the cover and putting the wire spring back into the divot on the metal crossbar, but it's concerning that it's possible for the belt assembly to fail in this non-obvious way. I've definitely noticed my kids sitting on the belt tail on multiple occasions, so I don't think this is just a theoretical problem.

To the original poster -- if you haven't already, please contact the NHTSA, and let us know what they (and Tesla) say.

 

[Fezzik]

I was able to reproduce at least a partial failure of the seat belt adjuster (i.e. got one of the two sides of the retaining wire spring to pop free of the divot on one side of the metal crossbar). To do so, I simulated the tail of the seat belt (the loose end) being trapped under the child's bum, and then applied moderate-firm force to the main part of the seat belt, pulling it towards myself (toward the back of the car) as if the child was leaning forward hard. The combination of this force with the seat belt tail being held trapped caused a torsional force to be exerted on the metal crossbar, which was sufficient to pop the spring free from one side. I heard a small metallic "ping", and on careful inspection it's visible (see red-circled area in photo below), but it would be easy to miss.

With one side of the spring loose, it may become possible for the metal crossbar to twist sufficiently to work loose, although I didn't observe that happening. It's possible that this is what happened in the original poster's situation, and when the sudden braking momentarily released tension, the seat belt adjuster came apart.

View attachment 70415

I was easily able to fix the seat belt adjuster by removing the cover and putting the wire spring back into the divot on the metal crossbar, but it's concerning that it's possible for the belt assembly to fail in this non-obvious way. I've definitely noticed my kids sitting on the belt tail on multiple occasions, so I don't think this is just a theoretical problem.

To the original poster -- if you haven't already, please contact the NHTSA, and let us know what they (and Tesla) say.

If it is not too much trouble, could you get a video of it at all? I think this would be extremely helpful. THanks!

 

[Zarwin]

If it is not too much trouble, could you get a video of it at all? I think this would be extremely helpful. THanks!

I just took a video of taking it apart to show how all the pieces work, but ran into something else. Will post the video shortly.

- - - Updated - - -

After looking at the assembly again, and trying to think of how the whole thing could come apart at once in the way OP originally described, I have a theory (got a little obsessed with this mystery). I'm convinced (unqualified opinion) that the tension wire must be unseated AND the cover must be off AND there cannot be tension on the assembly for it it come apart. The tension wire actually sticks out of the assembly a little where the top loops are. See pics here:

http://imgur.com/a/OONjN

If the tension wire were somehow caught on something that has a small hook and it was pulled on hard enough, it *might* be possible to pop the cover and unseat the wire at the same time. This could only come apart at one time if there was a traumatic incident that pulled the wire hard enough while the child was not putting tension on the belt, but OPs conditions do not rule out that rare sequence of events. Seems like an extremely unlikely sequence of events to cause this, but it might be possible.


EDIT: to clarify, the first pic is of the connector as it sits in the car, the edge of the loop is visible just looking at it. The second is with the anchor belt pulled back a little to show the full loop sticking out. Also, this is a connector I have never taken apart, not even the cover.

 

[Alysashley79]

Just a quick update my car is going in on Thursday to have the jumps seats replaced. I sent several pictures to the SC and they decided for safety not to replace the buckle portion but the entire assembly. (The seats are being sent up from th factory)

What we think happened is that the plastic piece that covers every thing is what failed and likely at some point (between Tuesday of last week and this past Sunday) broke off and then on Sunday the rest Came apart. I have no idea if it all failed at the same time or exactly how it happened since I can't see the kids sitting back there as I drive, all I saw was everything at the end...all the pieces were there (some on the floor mat) and a strap not anchored any longer.

Once the the seats are replaced and I can talk a bit more in detail with the shop foreman I'll update everyone. I'm also going to wait until this time to decide if I should get the nhtsa involved. I don't want in any way to be a "the sky is falling the sky is falling" person and I also feel like tesla has done everything they can to make our cars the safest cars in the world so if this is a design flaw I feel like they'll fix it. BUT if after talking to them on Thursday if I feel like that isn't the case I will definitely get them involved.

 

[ckessel]

I'm also going to wait until this time to decide if I should get the nhtsa involved.

Your choice of course, but I doubt Tesla manufacturers the seats and seat belts themselves in this case. Even if Tesla fixes it and assures you that they've never seen anything like it before, that doesn't mean other vendors buying from the seat manufacturer haven't had similar issues. I would at least ask how Tesla address such things with their vendor, something the service center probably doesn't know so you'd need to chase that up the command chain.

If you report it to NHTSA and it's a one-off, no harm done. If you report it and they do find a systemic issue, you may save a child's life.

If NHTSA never hears about it, the underlying vendor, should they choose to be unscrupulous, is given the chance to hide that the flaw occurred.

 

[CmdrThor]

Once the the seats are replaced and I can talk a bit more in detail with the shop foreman I'll update everyone. I'm also going to wait until this time to decide if I should get the nhtsa involved. I don't want in any way to be a "the sky is falling the sky is falling" person and I also feel like tesla has done everything they can to make our cars the safest cars in the world so if this is a design flaw I feel like they'll fix it. BUT if after talking to them on Thursday if I feel like that isn't the case I will definitely get them involved.

It seems fairly likely that Tesla would be required to report this sort of warranty claim anyways since it is seatbelt related. See all the fines the NHTSA dished out in 2014 for manufacturers failing to report injuries, warranty claims, recalls, etc: http://www.nhtsa.gov/About+NHTSA/Press+Releases/2015/DOT-fines-Honda-$70-million

 

[Skotty]

I'm just guessing here, but the design of the buckle is likely a fairly standard one that is used on belts in a lot more places than just Tesla Model S 3rd row seats. It's probably not Tesla's design, and is likely sourced from some other company that specializes in seat belts. I would bet on this being a one off case that was the result of either an unusual impact or pressure event while not in use, an assembly error, or less likely, a manufacturing defect. I would notify Tesla and have it taken in for service. Tesla service should probably replace it due to the sensitivity of safety concerns, and have the old one inspected, reviewed, and ultimately disposed of.

 

[Chris TX]

If they're replacing it with the same design, do they believe the design isn't flawed? I am also curious to know if and/or how it failed.

Also, for anyone thinking I'm trolling here, I also have the jump seats (see sig) and my two little girls ride back there all the time. I am just as concerned for their safety as any of you parents are on here for your kids. Dealing directly with Tesla and letting them handle it quickly is better for everyone than the long, drawn out process of getting the NHTSA involved. If the OP thinks Tesla isn't handling it properly or timely, then by all means get the NHTSA involved. Until then, let's at least give them a chance to act quickly and analyze the issue IF one exists. They are required to report it themselves, as someone else has stated.

 

[EchoDelta]

No, this is precisely why NHTSA exists.

Agree 100%
Reporting a factual explanation of what has happened is not a crybaby- sensationalist- treacherous move, and I'd expect whoever takes your call at Tesla would suggest you to do so too.

The alternate story "Tesla owners are such fans that they don't report safety issues to the NHTSA" would be much worse ... IMO.

 

[jerry33]

At the beginning of 2013, there was a rear seat bolt issue where some of the bolts weren't properly torqued and could cause the seat to fail in a collision. Tesla found and fixed the problem in a few weeks without the help of the NHTSA. They even wrote a blog about it. The skid plates, where the NHTSA was involved, took months to implement rather than weeks--a lot of the time appeared to be taken up with red tape rather than engineering. I'd rather have the problem fixed correctly sooner rather than later.

Agreed that if you have a car company that has a reputation for playing ostrich, you report everything to the NHTSA as soon as possible. When a company has a reputation for actually listening and fixing safety issues--even the ones you couldn't spot yourself--it really shouldn't be necessary.

 

[Chris TX]

At the beginning of 2013, there was a rear seat bolt issue where some of the bolts weren't properly torqued and could cause the seat to fail in a collision. Tesla found and fixed the problem in a few weeks without the help of the NHTSA. They even wrote a blog about it. The skid plates, where the NHTSA was involved, took months to implement rather than weeks--a lot of the time appeared to be taken up with red tape rather than engineering. I'd rather have the problem fixed correctly sooner rather than later.

Agreed that if you have a car company that has a reputation for playing ostrich, you report everything to the NHTSA as soon as possible. When a company has a reputation for actually listening and fixing safety issues--even the ones you couldn't spot yourself--it really shouldn't be necessary.

I completely agree with you, Jerry.

As Tesla owners, why would we trust a big wad of cash to a company to make the safest car in the world, choose to drive our families around in them, but then expect them to rest on their laurels and do nothing about this safety issue? Getting the NHTSA involved will put the brakes on any engineering fix that Tesla is coming up with.

"I'm with the Government and I'm here to help" Has anyone ever heard of that phrase?

Tesla has an excellent record for addressing potential safety issues in a rapid fashion and with full disclosure. Why start doubting, now?

 

[ckessel]

Tesla has an excellent record for addressing potential safety issues in a rapid fashion and with full disclosure. Why start doubting, now?

This has nothing to do with distrusting Tesla. This isn't about punitive action. It's about preventative action. It's about providing accurate data points for NHTSA to make broader decisions. The point has been made several times now by myself and others.

It sounds like, from other posts, Tesla is required to report any safety related problems to NHTSA anyway. Presumably that requirement is in place precisely so NHTSA can gather necessary cross-manufacturer data.

Getting the NHTSA involved will put the brakes on any engineering fix that Tesla is coming up with.

There's zero evidence that'd be the case. Now you're just inventing things from thin air out of anti-government zealotry.

 

[Chris TX]

This has nothing to do with distrusting Tesla. This isn't about punitive action. It's about preventative action. It's about providing accurate data points for NHTSA to make broader decisions. The point has been made several times now by myself and others.

It sounds like, from other posts, Tesla is required to report any safety related problems to NHTSA anyway. Presumably that requirement is in place precisely so NHTSA can gather necessary cross-manufacturer data.


There's zero evidence that'd be the case. Now you're just inventing things from thin air out of anti-government zealotry.

Actually, yes there is. Jerry just pointed out how long it took for the battery protection pieces to be delivered once the NHTSA got involved. Tesla moves faster when the gov't isn't involved. No need to get personal, here.