I've been thinking about adding these seat heaters so I've been watching these latest developments pretty closely. Tested my passenger seat today -- it seems that the sensor is in the middle of the seat (side to side) and about 3" wide or so. It runs from the back of the seat to the middle seam (front to back).

Is it possible that the airbag sensor somehow got moved when you reassembled the seat?

Very interested in the outcome, because I don't want to order the kit then have the problem.

yep you are right, the sensor is about 2 1/2 wide and about an 1 1/2 long. Its glued on the cushion and there really isn't much to them. I can't tell you much about them but the "sensor" itself is literally just a thin ribon type sensor that comes on and off when someone sits on it. Their may/may not be more to it.

The problem swooopeno is experiencing may be solely him. I noticed in more and more signatures here these heaters are showing up. And its not just these, lots and lots of people here have installed all kinds of heater kits in their rigs and not one of them experienced a problem like this.

I'll probably end up taking the cushion off this weekend (ahhhh!!!!) , and checking it out. One thing to note. The sensor you describe (T4rusaf) doesn't sound like mine. It 'appears' that I have two sensors. Each is about 1/2" wide, and runs from the back of the seat to the first seam. Almost looks like a 'U' shape when the cushion is off. Also, I have the Katskin after market leather. It's not a plush, soft leather like the limiteds come with. It's harder and tougher. I requested a leather that will hold up over time. Again, I don't think i've had problems with the seat belt blinker before. But now that I think about it more and more, it seems like the tiny sensors might have a problem under the thicker leather AND the heating element. I have some options though... if I find no problem with the sensors this weekend, I will just use the back heating element on the passengers side (if Rostra says it's ok to do that). I also have an email to Toyota regarding how the air bag deployment functions.

I will update as I progress.

ah i see, good deal. Yeah your sensor sounds like it is a a bit different than mine. I too have teh rostra seats and a custom leather kit. Lets hope you find something this weekend

ps - isn't it funny how this thread was for the most part dead, and then Oct. rolls around and its resurrected from the dead over the weekend? Figures though, it rained for the first time here in months!

Since I've not taken the seat apart, I don't know if it's a U or just a strip. But either way, it seems to cover about the same amount of area.

Sounds like you're on to something with the heater plus the heavier leather. Sure seems logical to me.

I'm looking to order and do this mod soon because we're getting to the time of year when the weather will cooperate, and before it gets cold. (not that the cold is that bad in Arkansas).



And thanks to you and the photos, looks like it should be pretty simple. Since I have an early production model, I have to be careful that all the wiring is there first.

Swooopeno -

Any updates to share?

I've blocked out some time this weekend to do it. The 85 degree weather hasn't put me in a huge rush... I did so some experimenting though. I had my lady ride a long taking her seat belt off and on, moving around in the seat. The sensor seems to work all the time EXCEPT (and it would be great if someone could do this that doesn't have them installed yet):

Tought to explain.. but i'll give it a shot... When you are sitting in the seat (seat belt off), and you put your feet flat on the ground nearest the seat, the sensor works. If you extend your feet to underneath the dash, thus placing more weight on the front of the seat (with your legs instead of your as$), the sensor thinks you're not sitting there anymore. Can someone else try this? I had someone else try it to in my 4R with the same result...

Tried it out tonight and saw no difference in the different positions you mentioned. Sensor worked as long as someone is sitting in the passenger seat.

It is getting cold in NJ and I was looking at this project again. From the posted Pics, the wiring doesn't look too bad. I have been in the console/armrest so many times I am not worried about that.

I am however a little concerned about putting the heater in the seat itself. How difficult and how do you access it.

THe first time I did it I just removed the hog rings under the seat and lifted the cushion and slid the element underneath. AFter I made sure that the element was straight and centered. THe back is similiar to the bottom cushion. I re-used the hog rings and closed them shut with some pliers.

The second time I did it I was in the middle of installing my leather so I took the cover off completely. Either way worked great for me

I contacted my dealer today, spoke to a service guy who actuall sounded like he knew what he was talking about. Asked him which sensor the airbag uses to deploy. His first question was if I had an airbag on/off light, which I don't. He said I don't have the latest and greatest 'smart air bags'. He said because of this, he thinks all air bags deploy in an accident. The only thing the sensors are for are to remind passenger to buckle up. This was good news for me, but I am still going to call at least a couple other dealers to see if I get the same answer.

Hey you '05 and '06'ers.... do you have an airbag on/off light? If so, can you check something out... does it stay 'on' even if passenger does not have seat belt on?

I do have a airbag on/off light, and it seems to work independent of the seatbelts and seatbelt light. Must be two switches?

OK... another update...

Called another dealer, and got a hold of someone at toyota customer care that knew something.

dealer said he thinks '02 and up rely on the weight sensor to deploy the airbag. Prior to that, both airbags deploy. Customer care said something similar.

I guess that's enough for me.

Option 1. I think the weight sensor is just sticky backed to the seat cusion. I could remove that and place it on top of the heating element? I'll call Rostra on that one.

Option 2. Remove seat heating element all together. Can only the back be hooked up or will it overheat? I'll call Rostra on that too.


Ahh... bad news day... oh well. Should have got the limited in the first place : (

But as far as the Smart air bags, there were two versions developed. (one pre-requirement, one post requirement, the air bags before the smart bags would deploy regardless of passenger or not)

The first smart air bag had a seat sensor that would switch it off if the person sitting in the seat didn't weigh the minimum (70lbs I think). Because of the decapitations and injuries that airbags have caused a couple years ago the feds mandated that a new type of smart airbag be deployed (not sure what model year it was mandatory) This new smart airbag requires that the sensor not only detect the weight of the person but coordinate with the seatbelt sensor and adjust the deployment of the bag based on the results. In other words a 90lb woman buckled up sitting in the seat vs a 300lb man unbuckled is going to have dramatically different deployment rates in the bag varying from 20mph to 200mph based on the characteristics of the person sitting there. Airbags are actually very dangerous if you don't fit the profile of the test subject (190lb, 5'10" male) and smart airbags are supposed to solve that problem.