Tech Question - Passenger Airbag Light

[cx5diesel]

Hello all,

I am new to this forum - was looking at a CX-5 diesel today and fell in love with it. One problem I am hoping some tech expert may be able to help with. My passenger needs to use one of those seat pads that has a tailbone cutout in it. Apparently that is exactly where the passenger sensor in the seat is, so we were driving with the "Passenger Airbag Off" light on. So, here's my question:

Is there a way to code this out so that the passenger airbag always stays on? Dealer will not do for liability reasons.

or

2. Is there a way to short the sensor itself easily to make it always think someone is in the seat?

Thanks in advance.

 

[Mazdiod2]

Maybe you can fake it out with a piece of : carpet? Upholstery foam?

Something you can put under the cushion where the cutout is. Might be better than messing with the wiring.

 

[Avoidin Deer]

Interesting that having the airbag always ON might present a liability issue.

Lots of folks here have complained that the seat sensor is too sensitive...that a small package on the seat is seen as a human.

I would think you could find something small enough and just heavy enough to do the trick.

By the way: read some of the posts here about pricing on the CX-5 diesels. They are being reduced by up to $10,000 dollars. Mazda is not going to be making them in 2020.

Read this thread.

Start at the end and read forward...the price reductions are the most recent conversations.

 

[cx5diesel]

Thanks for the feedback on the airbag and the pricing. I've seen as high as $8200, but $10K would be much better! I have another seat pad I think I will try, and I will also try the part about adding something to the other pad to see if that helps.

 

[sm1ke]

I'd try cutting out a 1/8" thick piece of plywood and putting it under the seat pad. That way, when your passenger sits on the pad, the weight is distributed evenly and the sensor is triggered. The only issue would be the wear on the seat due to the wood, but you could fix that by getting a seat cover or putting a thick towel down.

 

[COmtn]

The seat uses a heat sensor, not weight, to determine if someone is there.

 

[Avoidin Deer]

The seat uses a heat sensor, not weight, to determine if someone is there.

You're close.

This is from my manual:

Your vehicle is equipped with a front passenger occupant classification sensor as a part of the supplemental restraint system. This sensor is equipped in the front passenger's seat cushion. This sensor measures the electrostatic capacity of the front passenger's seat.

I sure thought that there have been people complaining that the seat sensor is so sensitive that even a purse or small bag of groceries placed there turns on the passenger air bag system. Maybe I misremembered.

 

[cx5diesel]

Very interesting. "Definition of electrostatic capacity. Quantity of electricity needed to raise system one unit of potential." I wonder what, exactly, what means. Any ideas?

 

[sm1ke]

The seat uses a heat sensor, not weight, to determine if someone is there.

You're close.

This is from my manual:



I sure thought that there have been people complaining that the seat sensor is so sensitive that even a purse or small bag of groceries placed there turns on the passenger air bag system. Maybe I misremembered.

I stand corrected, my mistake.

 

[RedBaron]

Very interesting. "Definition of electrostatic capacity. Quantity of electricity needed to raise system one unit of potential." I wonder what, exactly, what means. Any ideas?

The seat presence detector works by having sets of dual electrodes spread about like little antennae. The capacitance across the electrodes changes in the presence of mass+liquid and the controller can determine the mass at each point across the seat face to calculate the presence of a body and the weight of the body. It's a very similar mechanism to the multi-touch capacitive touch screen on your phone - or the car radio.

 

[cx5diesel]

This is all helpful. I've been able to find some interesting discussions on other car forums about this. One suggests wrapping the pad with grounded aluminum foil. I am going to keep digging. In the meantime, please keep the ideas coming!

 

[cx5diesel]

OK, for anybody else that has this issue, looks like someone on a Subaru forum has found a solution.

Here's the link: https://www.subaruforester.org/threads/using-seat-cushion.694122/

Essentially you use a special metal fabric used for blocking something electrical (non technical explanation)

Here's an example on Amazon:

https://www.amazon.com/dp/ (commissions earned)

 

[Avoidin Deer]

I stand corrected, my mistake.

No, man, I wasn't correcting you.

Your answer was way more accurate than mine. I'm still confused regarding packages being mistaken for people.

Maybe older models work differently.

 

[cx5diesel]

Juat as a side note, there are no issues with the pillow and the seat in my 2019 Honda Civic. It must use a different type of sensor.

**edit** I just read the owner's manual. On my Civic, it simply uses a weight sensor.