Attention: TDR Forum Junkies 
Sometimes a little knowledge can be a bad thing.
I've been thinking about putting in the Rostra seat heaters from Geno's I'd be going all out doing the driver's seat of course, plus two for the rear bench to cut down on the whining in the morning taking the kids to school. The problem is the passenger seat. Doing a little research in the '06 Service Manual on how the factory does it I came across this warning under the Heated Systems / Heated Seats section:
WARNING: The front passenger seat assembly contains critical components that affect the front passenger airbag deployment. Correctly functioning front passenger seat components are critical for the Occupant Classification System (OCS) to properly classify the front passenger and calculate the proper airbag deployment. Unapproved modifications or service procedures to the front passenger seat assembly, its related components, or trim cover may inadvertently change the airbag deployment in case of a frontal crash. This could result in death or serious injury to the front seat passenger if the vehicle is involved in an accident.
The following requirements must be strictly adhered to:
² Do not modify the front passenger seat assembly or components in any way.
² Do not modify the front seat center console or center position seat in any way.
² Do not use prior or future model year seat trim covers not designated for the specific model being repaired. Always use the correct seat trim cover specified for the vehicle.
² Do not replace the seat trim cover with an aftermarket trim cover.
² Do not add a secondary trim cover other than those approved by DaimlerChrysler/Mopar.
² At no time should any Supplemental Restraint System (SRS) component or SRS related component or fastener be modified or replaced with any part except those which are approved by DaimlerChrysler/Mopar.
Sounds pretty strict. I've heard of airbag systems that can sense the weight of the occupant and adjust the force of airbag deployment accordingly and the warning sounds like it's trying to keep you from messing that system up. However looking in other sections of the service manual like the Body / Seats section and going through the whole Restraints section I can't find a single thing in them to back that up. I would think the section in the manual covering plain unheated seats would have the same warning as found for the heated seats but it doesn't. In the Restraints section the only thing I could find on the seats is that some have a sensor for seat position on the rail, nothing about sensing weight.
So I went and looked under the seat and yes there is a sensor under the passenger seat only. It has an attached label that says it is a weight sensor and if it is messed with it must be recalibrated by a properly trained technician or bad things may result. (obviously my wording, I can't remember the exact words and don't feel like going out to look again)
So now my interest is really perked up. This sensor is about a 1/2 inch square attached to the end of a standard wiring connector. It is mounted to a piece of flat stock about 2" wide that spans between the two seat rails with the sensor in the middle on the forward edge. At first I thought it might be a hall effect sensor detecting the proximity of the seat bottom's support grid and springs but the jack and all the tire wrenches sit right next to it and all that metal would have a greater effect on a hall effect sensor than the metal of the seat cushion springs. So my curiosity of how this thing works is peaked.
Googling for info on this sensor doesn't come up with much. I found a small reference to people getting the Passenger Airbag Off light and one of the solutions was to have the weight sensor calibrated and something about them using three weights in the process. (other solutions was to not put your briefcase/shopping/purse... on the pass. seat)
So what am I asking?
1) Will the installation of a seat heater on the passenger seat adversely effect the airbag system performance? (I figure if it does anything it will make the seat cushion stiffer and thus appear there was less weight in the seat than there really is. This might cause the airbag to be deployed for a lower weight passenger and thus might not be as effective as possible, not a good thing)
2) Can the heater be installed and the weight sensor simply be recalibrated?
3) Why is there nothing in the Service Manual about this sensor, nothing about it's installation, operation, calibration. (kind of a rhetorical question I suppose)
4) Any other suggestions?
I've been thinking about putting in the Rostra seat heaters from Geno's I'd be going all out doing the driver's seat of course, plus two for the rear bench to cut down on the whining in the morning taking the kids to school. The problem is the passenger seat. Doing a little research in the '06 Service Manual on how the factory does it I came across this warning under the Heated Systems / Heated Seats section:
WARNING: The front passenger seat assembly contains critical components that affect the front passenger airbag deployment. Correctly functioning front passenger seat components are critical for the Occupant Classification System (OCS) to properly classify the front passenger and calculate the proper airbag deployment. Unapproved modifications or service procedures to the front passenger seat assembly, its related components, or trim cover may inadvertently change the airbag deployment in case of a frontal crash. This could result in death or serious injury to the front seat passenger if the vehicle is involved in an accident.
The following requirements must be strictly adhered to:
² Do not modify the front passenger seat assembly or components in any way.
² Do not modify the front seat center console or center position seat in any way.
² Do not use prior or future model year seat trim covers not designated for the specific model being repaired. Always use the correct seat trim cover specified for the vehicle.
² Do not replace the seat trim cover with an aftermarket trim cover.
² Do not add a secondary trim cover other than those approved by DaimlerChrysler/Mopar.
² At no time should any Supplemental Restraint System (SRS) component or SRS related component or fastener be modified or replaced with any part except those which are approved by DaimlerChrysler/Mopar.
Sounds pretty strict. I've heard of airbag systems that can sense the weight of the occupant and adjust the force of airbag deployment accordingly and the warning sounds like it's trying to keep you from messing that system up. However looking in other sections of the service manual like the Body / Seats section and going through the whole Restraints section I can't find a single thing in them to back that up. I would think the section in the manual covering plain unheated seats would have the same warning as found for the heated seats but it doesn't. In the Restraints section the only thing I could find on the seats is that some have a sensor for seat position on the rail, nothing about sensing weight.
So I went and looked under the seat and yes there is a sensor under the passenger seat only. It has an attached label that says it is a weight sensor and if it is messed with it must be recalibrated by a properly trained technician or bad things may result. (obviously my wording, I can't remember the exact words and don't feel like going out to look again)
So now my interest is really perked up. This sensor is about a 1/2 inch square attached to the end of a standard wiring connector. It is mounted to a piece of flat stock about 2" wide that spans between the two seat rails with the sensor in the middle on the forward edge. At first I thought it might be a hall effect sensor detecting the proximity of the seat bottom's support grid and springs but the jack and all the tire wrenches sit right next to it and all that metal would have a greater effect on a hall effect sensor than the metal of the seat cushion springs. So my curiosity of how this thing works is peaked.
Googling for info on this sensor doesn't come up with much. I found a small reference to people getting the Passenger Airbag Off light and one of the solutions was to have the weight sensor calibrated and something about them using three weights in the process. (other solutions was to not put your briefcase/shopping/purse... on the pass. seat)
So what am I asking?
1) Will the installation of a seat heater on the passenger seat adversely effect the airbag system performance? (I figure if it does anything it will make the seat cushion stiffer and thus appear there was less weight in the seat than there really is. This might cause the airbag to be deployed for a lower weight passenger and thus might not be as effective as possible, not a good thing)
2) Can the heater be installed and the weight sensor simply be recalibrated?
3) Why is there nothing in the Service Manual about this sensor, nothing about it's installation, operation, calibration. (kind of a rhetorical question I suppose)
4) Any other suggestions?
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I don't know what was wrong with the simple manual switch method. Oh, wait, someone probably was afraid of getting sued. I swear, protecting against litigation is going to be our doom. 
