You guys are hilarious. Well, my girlfriend weighs just over 100 pounds, and I'm sure the sensor in the seat thinks it should turn off the airbag. But, I want her to be safe at all times! And sometimes the light is on in the daytime while we're driving, and we don't notice it.

So with that being said, is there any way to DECREASE the sensitivity of these sensors? Also, what about the little vent/microphone looking things all over that side of the car? Those are related to the airbag too, right? If not, what are they?

 

But if she's a weight where it's unsafe to deploy the airbag, you don't want to fool it!

Do you mean the ultrasonic sensors? Or temperature sensors? Have a hunt round jtis

 

My girlfriend is an adult, it would not be unsafe to deploy the airbag while she is seated in the front seat. Anyone know anything about the sensors either in the seat or otherwise that control this function (feature?). Thanks in advance.

 

I would assume that the seat sensors don't go bad very often and that is why others aren't chiming in on this. Did you test other people in the seat like I suggested? There is no adjustablity that I am aware of. A dealer would be best to answer that one. If the lamp is lighting up no matter who is in the car then it would point to a bad sensor or something else. Another thing to remember, it also factors in the seat position. It will lower its threshold if the seat is up close to the dash. It also does that on the driver's side as well. It won't shut off the driver's air bag, but will lessen it's force based on seat position. Remember when people were getting hurt by airbags way back when? This is why there are so many sensors involved now.
Now about all the little round discs... JagV8 is right, they are a mix of ultrasonic, and temperature sensors. JTIS is a great tool to find out about them. It is a little tedious to navigate but worth it. Those sensors are for the climate control and anti-theft systems.

 

pantheon - I was very much hoping, and indeed assuming, she was an adult! But the matter of safety does not depend on that. I really cannot say more than that it would be incredibly unwise to bypass a safety feature. It would certainly invalidate your insurance unless you declare to them what you have done and get their agreement in advance of having any passenger in the car.

 

Yes, I had a friend of mine drive around with me, (he weighs about 220), and the light only came on once, while I was turning (shift in weight, no doubt caused it). So I guess I'm going to have to try to figure out where the sensor is located in the seat, and try to hone in on that to see if I can fix it.

 

hellloooooo? are you serious?????

 

I'm not sure where Jag's frustration is, but I have to ask a question. Are you looking for the sensor to deactivate or to replace? I ask because the light should not come on at all with a 220lb person in the passenger seat. That would tell me that something is out of whack. Also, I'm pretty brave when it comes to working on my own stuff, but this one would be at the dealer to check. I would be afraid I'd make it worse without the proper equipment to check all the various sensors that control the airbags. What ever you do, don't deactivate the system, get it fixed.

 

that was what I meant

 

Is the dealer going to charge me $125 to look at it?

 

That's really up to the dealer to decide. My experience is that isn't a "fixed" cost. Some dealers charge less for diagnostic fees than others. Others waive the fees if you get the service done there. If you have a good customer relationship with the dealer, they may not charge you anything to check it out. How is your relationship with your dealer? If you don't have one, I would recommend you build one. That isn't just Jaguar advise, but applies to all makes. You never know when you may be in need of the specialized knowledge of the service department. I have done that with all the different cars I've had and my negative dealer experiences have been minimal. Amazing what a little light conversation and maybe a dozen donuts or two will do. Given the sensitivity of your issue, I would definitely seek out the dealer if it was my car.

 

+1 on the ^^ advice.

 

I just want the passenger airbag to always be on. There's no reason I can think of that it should be off if there is a passenger (who's not a child) riding in my passenger seat. I never have kids riding in my car, but if I do, I'll make sure they sit in back. Anyway, I'm going to talk to the dealer about this soon. I'm not trying to endanger anyone, I'm trying to keep my girlfriend safe in case of an accident.

 

I know we seem a little passionate about this, but it is all with the best intentions. I'm glad to hear you are getting it to a dealer. Your issue is not a common one and these systems are way more complex than people think. You are right in your statement that the airbag should be on with anyone but a child on board.... BTW... I have one child up front a lot lately, but that happens when you have three kids and a narrow back seat. Good luck and be sure to update us when you find out what it is..Updating is one of the best ways to increase the knowledge base on here.

 

The handbook covers Occupancy Sensing but doesn't define "low weight", so maybe you can find out the threshold value.

Maybe low weight is less than 200lbs or even 280lbs?

 

With regards to passenger airbags, my 1999 Volvo S80 did not have one. As a result it scored 4 stars (out of a maximum 5) in the NCAP European safety scoring system. But Which? consumer magazine gave it 12.5 points in its safety rating system, which was about 2 points more than any other car at the time. The Which? rating system has no maximum, the points go up as more safety devices are introduced. (The S-Type was the first car to get 13 points).

The reason why Volvo did not have a passenger airbag was that because of the shape of the dashboard it was going to have to be so big that that was going to cause other issues. Furthermore, with seatbelt pre-tensioners and a headrest that actively contributed to whiplash reduction, an airbag becomes redundant. They did eventually introduce one, but only after they were satisfied with a sensor system that would only activate if a particularly large person was in the seat. That has the advantage of keeping repair costs down as you can imagine the damage done to the dashboard.

The following are assumptions. If Jaguar through crash test results have found the same as Volvo, then they want the passenger airbag to only go off in the most catastrophic of accidents. I dont know if they have seatbelt pre-tensioners and the headrests do not feel as anti-whiplash as the Volvo ones. I also do not know if the drivers side airbag is sensor activated, so it deploys based on the drivers size. But if all of the above is the case, then the passenger airbag is not as essential as you would imagine.

But, to get that all important NCAP 5th star all manufacturers put in a passesnger airbag. Volvo have been critical of NCAP. They argue that its tests are too basic and other manufacturers have build their cars to meet NCAPs specific tests only.

Airbags have become far more intelligent. The UK car programme 5th Gear crashed two Renault Espaces (large people carriers) into each other. One was an original, the other a new one. The original suffered major front end damage and both airbags went off. The test showed that the passenger airbag would not have touched the passenger. It was a right off. The new one's airbags did not even go off.

So Jaguar have an intelligent airbag system. Maybe the mistake was to put the light on the dash. It becomes a distraction.

Incidentally I know someone who ran into the back of a bus at about 10 mph. The airbag went off, her jumper caught on fire and she had burns to her arm.

 

Damage to lungs from inhaling the burning gas is another serious risk.

The odd thing is that plenty of people worry about having lots of airbags yet still do not even make sure their passengers use the seat belts (regardless of any laws about doing so).

There again, if you're not using the selt belt you kinda need airbags

 

My airbag warning light just started acting up. I did some twiddling with the seat by moving it up vertically and then jiggling a 1/4" cable or wire that can be reached from the back. This seemed to fix it. Apparently there are a couple of places that can cause this fault, in the steering column or under the seat. At least in my case it appeared to be under the seat. I also adjusted the seat so it wasn't as low as it normally is so hopefully that is the final fix. One option to check for those that have this issue.

 

The ones near/under seats are notorious for eventually becoming poor connections on many cars, and you've done the right thing

Lots more connectors go the same way but only some are critical. Any of them can usually be fixed by breaking and re-making the connection a few times if only you can find the connector concerned!

This applies to fuses and relays, too.

Can be a very cheap fix.
Not always a quick fix.

 

On my 2003 S-Type, I had an airbag flash code of 19. It turned out to be a pin that had fallen out of the connector body on the airbag cable connected to the clocksping (spiral cassette). I gently bent the retention tab on the pin and snapped it back in. The clockspring did not need to be removed to do this, but I did have to pull the steering wheel off to get access.