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Old 11-18-2013, 01:09 PM
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Does the WK2 not have a psngr airbag weight sensor?

I.e. it won't inflate if the sensor doesn't sense at least 65lbs or something like that? I cannot find the answer in the manual. tia
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Old 11-18-2013, 01:17 PM
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Re: Does the WK2 not have a psngr airbag weight sensor?

It seems they've gone beyond a weight/pressure switch.

"NOTE: The Driver and Front Passenger Advanced Front
Air Bags are certified to the new Federal regulations for
Advanced Air Bags.
The Advanced Front Air Bags have a multistage inflator
design. This allows the air bag to have different rates of
inflation based on several factors, including the severity
and type of collision.
This vehicle may be equipped with driver and/or front
passenger seat track position sensors that may adjust the
inflation rate of the Advanced Front Air Bags based upon
seat position.
This vehicle may be equipped with a driver and/or front
passenger seat belt buckle switch that detects whether
the driver or front passenger seat belt is fastened. The
seat belt buckle switch may adjust the inflation rate of the
Advanced Front Air Bags.
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Old 11-18-2013, 07:58 PM
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Re: Does the WK2 not have a psngr airbag weight sensor?

Quote:
Originally Posted by bill_de View Post
It seems they've gone beyond a weight/pressure switch.
These only talk to sensors that affect inflation rate, not whether they disable the bags at all. Basically they're saying that if the seat is all the way forward and the belt is fastened, you may get a different inflation speed than if the seat was all the way back and the belt unfastened (as a comparison of extremes).
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Old 11-19-2013, 12:05 PM
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Re: Does the WK2 not have a psngr airbag weight sensor?

I wonder what changes with the seatbelt buckled vs not? More airbag pressure to compensate for unrestrained numbskulls in the seat or less airbag pressure to lessen injuries to unrestrained numbskulls. Maybe it disables the airbag altogether if the belt isnt buckled to thin the herd.

I like that it dings and says which belt isnt buckled. I can just point at the screen as a gentle reminder to tell my wife to put it on.

Ive had the screen indicate "buckle passenger seatbelt" when a heavy box was placed on te seat. So i think the weight sensors are still there.
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Old 11-19-2013, 12:19 PM
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Re: Does the WK2 not have a psngr airbag weight sensor?

Quote:
Originally Posted by Bikemobile View Post
I wonder what changes with the seatbelt buckled vs not? More airbag pressure to compensate for unrestrained numbskulls in the seat or less airbag pressure to lessen injuries to unrestrained numbskulls. Maybe it disables the airbag altogether if the belt isnt buckled to thin the herd.
IANAABE -- I am not an Air Bag Engineer.

I do not know how air bags work in detail, specifically "smart" air bags. Generically, air bags work by setting of a sort of "explosive" to create the gas to fill the bag. I imagine a "smart" air bag has several charges, perhaps of different sizes and thus can fire "a lot" (i.e. all the charges), "a little" (some of the charges), or it can stage the charges, fire one to start initial inflation, based on timings (such as initial speed or declaration rate) it can fire the charges in sequence, "firming" up the bag as you fall in to it.

So, with an un-restrained person, it's better for them to hit a softer bag initially just to catch them and then firm it up once they're settled, rather than inflating it to FULL initially, because unrestrained people have an issue of "bouncing off" the fully inflated airbag.

The net result may be less effective, but it's more effective than being bounced of completely and lawn darting in to the center console or a door pillar.

Again, I'm making all this up. I could be completely wrong, but sounds good to me.
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Old 11-19-2013, 12:20 PM
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Re: Does the WK2 not have a psngr airbag weight sensor?

Quote:
Originally Posted by whartung View Post
These only talk to sensors that affect inflation rate, not whether they disable the bags at all. Basically they're saying that if the seat is all the way forward and the belt is fastened, you may get a different inflation speed than if the seat was all the way back and the belt unfastened (as a comparison of extremes).
True, but I figured that was enough information for you to find a more specific answer. In part, from safecar.gov;

"7. Are advanced frontal air bags the same as "depowered" air bags?
No. In 1997, NHTSA allowed manufacturers the option to reduce the inflation power, or aggressiveness, of 1st generation air bags to lessen the likelihood of an air bag-related injury. These less powerful air bags are known as "depowered" air bags and have been in most vehicles since 1997. Advanced frontal air bag systems are a next-generation air bag system designed to be even more effective than the current depowered air bags in saving lives, while at the same time minimizing the likelihood of an air bag-related serious injury or death"
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