TEL51 Posted January 9, 2015 Share Posted January 9, 2015 Help! My wife and I want to purchase a new 2015 Forester. In fact, we had one picked out and ready to take home but had to cancel the deal. Here's the problem. My wife has a bad back. She needs a seat cushion that levels out the car seat as well as a separate lumbar cushion. When she sits on her preferred seat cushion. the passenger side airbag sensors won't recognize that someone is sitting in the passenger seat and, therefore, the airbag is shown as being "Off". We've tried everything we can think of to solve this problem. Different seat cushions of varying configurations. Any cushion that we've tried that "levels" the seat completely covers the airbag sensors. Seat cushions that don't cover the sensors are either too short or too narrow and are uncomfortable. The dealers talked to their Subaru technical contacts who couldn't provide a solution. The dealer suggested the possibility of going to a specialty company that does mobility-related modifications (which, of course, Subaru wouldn't warrant). Trouble is we really don't want to take the risk of anyone messing with the technology plus the fact we would have to purchase the vehicle not knowing for sure that modifications could be done. Any suggestions on what we can do so we can join the Subaru family. I was thinking that there might be something that I could insert inside the cushion cover (on the bottom of the cushion between the cushion cover and the foam insert) that would "set off" the sensors and turn on the airbags. Something that would not do any damage to the seats or the sensors. I read where certain electronic devices sitting on the passenger seat cause the airbags to turn on, but my wife doesn't particularly want to buy an iPad to insert into the seat cushion. Assuming one of you comes up with a workable solution, I just want to verify one other thing. I assume the same problem would not exist when my wife is driving the car since I would guess that the driver side airbag is always activated when the vehicle is turned on. Quote Link to comment Share on other sites More sharing options...
Fairtax4me Posted January 9, 2015 Share Posted January 9, 2015 (edited) My guess is the device you have sits up too high on the seat bolsters and doesn't put any (or maybe just not enough) weight on the occupant weight detection sensor in the bottom of the seat. There are also weight sensors in the back part of the seat on some new vehicles so the occupant detection system can tell if there is a person in the seat, or just a box or heavy bag which will not put weight against the rear of the seat. In that case both sensors need to see a certain amount of weight for the passenger airbag to be enabled. The best thing you could try is put a separate block of heavy foam under the special cushion. Something thick enough to make up the space difference between the top of the bolsters and the center of the seat. Go to a fabric store and get a section of foam roughly that thick and cut it to fit in the center of the seat between the bolsters and that will place her weight on the center of the seat where the sensor is, rather than on the bolsters. Cut another section to put behind her lumbar support if the bottom section doesn't work by itself. It shouldn't cost much, so if it doesn't work you're not out a bunch of money. As far as I know, yes, the drivers airbags will always be active. Occupant detection systems are designed mostly to prevent unnecessary deployment of airbags (passenger, side, rear airbags) when there are no passenger occupants to protect. Airbags are expensive, and having 4 go off vs just one (for the driver) can make the difference between a totaled car and a repairable one. Airbags also tend to have a fairly violent and LOUD deployment. They can send things flying. Say you have a box of stuff, or a bag of groceries in the front seat. You don't want those bouncing off of a deploying airbag and flying toward you. Edited January 9, 2015 by Fairtax4me Quote Link to comment Share on other sites More sharing options...
TEL51 Posted January 9, 2015 Author Share Posted January 9, 2015 We've been told that the 2015 Forester airbag sensors are not based on weight . . . that's what's causing our problem. Apparently, whether the airbag is turned on or off is based on an "Electrostatic Capacitance Sensor". I don't know when the change-over occurred, but the new sensor is present in the 2015. The 2015 CRV is still based on weight and is our second choice if we can't find how to make the Forester work. Quote Link to comment Share on other sites More sharing options...
keith3267 Posted January 9, 2015 Share Posted January 9, 2015 Not based on weight? How does it tell the difference between a child and an adult? The whole reason for the sensors was to not deploy the air bag if a child was in the seat. Quote Link to comment Share on other sites More sharing options...
TEL51 Posted January 10, 2015 Author Share Posted January 10, 2015 (edited) I don't know how it tells a child vs. an adult. However, we've been told the same thing by the sales person and the sales manager. I also called the Subaru 800 number and they confirmed. I also downloaded the pdf manual for the 2015 Forester. The following statement appears on page 1-46 of the manual: "The occupant detection system sensor is installed under the seat upholstery and monitors the physique and posture of the passenger. Using this information, the occupant detection system determines whether the front passenger's SRS frontal airbag should be deployed or not." Finally, when we were testing different seat cushions, we would remove the cushion and sit directly on the seat and the airbag would show "On" and when we put the cushion back and sat on the cushion the sensor would show "Off". It also didn't matter whether my wife was sitting or the cushion or I was sitting on the cushion (I weigh 180 lbs). Bottom line - it's definitely not weight that determines the passenger airbag on/off status -- at least it's not for the 2015 Forester. P.S. Just found the following site which describes the system for the Impreza and BRZ. Although it's a 2012 article, seems like the same technology is now employed on the Forester. http://www.stanleysubaru.com/blog/2012/august/6/how-does-the-occupant-detection-system-ods-work-in-my-subaru.htm Edited January 10, 2015 by TEL51 Quote Link to comment Share on other sites More sharing options...
Fairtax4me Posted January 10, 2015 Share Posted January 10, 2015 Interesting read, thanks for posting the link. So it appears all you need is a material with surface capacitance roughly similar to that of human skin... Find a body somewhere, skin it, paste the skin to the seat, then put your cushions over it! Easy! Kidding! Don't skin anybody please! That's pretty creepy to think about... Like the article said, a laptop sitting on the seat may enable the system, but a wet body (even a wet passenger) will not enable the system. I think an electrical device could be rigged to fool the system. A low voltage/ low level current run through a sheet of copper or aluminum, or a flat coil of copper wire might work. Cover it with a layer of denim or other material that pants may be made of. I always like the low tech approaches though. Somewhere out there there must be a material (rubber/plastic/synthetic) that has capacitance similar to a human. I wanna say Mythbusters did an episode on the effects of electricity through people (busting myths about electrocution) and used dummy's made from some kind of rubbery stuff that was suppose to have similar electrical properties to a real person. 1 Quote Link to comment Share on other sites More sharing options...
nipper Posted January 10, 2015 Share Posted January 10, 2015 Interesting read, thanks for posting the link. So it appears all you need is a material with surface capacitance roughly similar to that of human skin... Find a body somewhere, skin it, paste the skin to the seat, then put your cushions over it! Easy! Kidding! Don't skin anybody please! That's pretty creepy to think about... Like the article said, a laptop sitting on the seat may enable the system, but a wet body (even a wet passenger) will not enable the system. You know what may work, a piece of suede to go between the seat and the cushion. Real sued is just animal hide. Quote Link to comment Share on other sites More sharing options...
TEL51 Posted January 10, 2015 Author Share Posted January 10, 2015 (edited) Don't think suede or any type of leather would work. Otherwise, the leather seats of the Touring would set off the sensors. Many laptops and all tablets are touchscreens these days and touchscreens are, I believe, based on capacitance. That's probably why they activate the sensor. As was suggested, some kind of electrical device could probably fool the sensors, but I would prefer to go with something more low tech as well. Wonder what material they use to make a stylus which works on a touch screen. Also, certain materials that have a lot of static electricity in low humidity conditions might work, but that would only help sometimes so is not practical. We really need an electrical engineer to chime in with some thoughts -- or maybe someone who can speak to the Subaru tech people who designed the system. We really want to buy the Subaru, but will have to go with our second choice soon if we can't find a solution. Edited January 10, 2015 by TEL51 Quote Link to comment Share on other sites More sharing options...
keith3267 Posted January 10, 2015 Share Posted January 10, 2015 (edited) Looks like a major lawsuit in the making here. There are so many ways to fool the system. Looks like Subaru is hiring graduates from the Rube Goldberg school of engineering. The weight sensors worked just fine, but since wet clothes, cushions and laptops can confuse the system, the airbag may either deploy when it shouldn't or not deploy when it should. The electric parking brake is going to bite them in the backside eventually too. I hate it when poor engineering gets past management and into products. The dealer says they can't override the system and the reason is not physical but legal. If they override the system, and the owner (or subsequent owner) puts a child in the front seat, the airbag could deploy on a minor accident and injure or kill the child. They will not take on this liability. Your options might be to see if the seat can be retrofitted with the older pressure sensor, or if a seat from an older Subaru can be substituted. Maybe a seat from a 2014 Legacy. Next would be a custom upholstery shop that could re-pad your seat to your specifications and move the sensor to a location where it still works. Edited January 10, 2015 by keith3267 Quote Link to comment Share on other sites More sharing options...
nipper Posted January 10, 2015 Share Posted January 10, 2015 (edited) A little more info http://electronicdesign.com/components/sensors-measure-emerging-automotive-safety-standards Have you asked any of these for input? http://www.subaru.com/owners/resource-center/mobile-it-ease.html Edited January 10, 2015 by nipper Quote Link to comment Share on other sites More sharing options...
TEL51 Posted January 11, 2015 Author Share Posted January 11, 2015 A couple of problems with Subaru's "Mobile-It_Ease" program is that the form you have to fill out says Subaru bears no responsibility for any modifications. Also, you have to purchase the vehicle first and then make any modifications. What if the changes don't work or are problematic in some way. Your're stuck with a vehicle that doesn't meet your needs and you have to immediately resell it at a big loss. Frankly, too big of a hassle. I checked one thing out. Stylus tips are made from conductive silicone rubber. You can buy sheets of that material and they may work, but the material is not available locally to try out. I'd have to buy some from the manufacturer and have it shipped. Again, big hassle. The CRV is my second choice by just a little bit and I'm thinking that that's the direction I'll go. By the way, my research also turned up the fact that someone wearing a heavy coat might result in the airbags not activating. I wonder how many Subaru owners out there would notice that the airbag is "Off" when there passenger is wearing a heavy coat. It's something you might not notice and it's not like a lot of people are even aware of this technological change and the potential problems. After all, two of you who responded to this thread are obviously Subaru enthusiasts (based on the number of posts), but were unaware of the demise of the weight-based sensors. Maybe a warning should be pinned on this site to give owners a heads up. Thanks for your help guys. Maybe by the next time I need to replace a vehicle there will be some solution to the problem. Personally, I would recommend that Subaru have the current setup being the default when a vehicle is turned on, but have an override switch to turn on the airbag system if the situation warrants. By requiring the owner to take an action to override each time they turn on the vehicle, I would think that would put the responsibility on the owner if they turned it on when they shouldn't. Just a thought. Quote Link to comment Share on other sites More sharing options...
nsavignac Posted January 28, 2017 Share Posted January 28, 2017 I have experienced the same problem with my 2016 Forester,i.e., the passenger airbag will NOT turn on when my wife sits on an air cussion in the passenger seat. Solution: Purchase a "WIFI Blocking Nickel/Copper Fabric" (24" X 15") from amazon for $18. Place the fabric under the air cussion and the airbag will come on when someone sits in the seat. Nobody in the seat and the airbag is off. I fabricated a pillow case with the metalic fabric sewed inside and place the air cussion in the pillow case. ( I aasume no liabilities for passing on what I experienced). Christmas16. Quote Link to comment Share on other sites More sharing options...
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