bebbetufs

I have a 97 986 with a 98 body. Checking the PET the 2 and 4 bag cars have the same serial no. for the Temic airbag computer. To me this indicates that the number of airbags is determined in the software. Could anyone confirm if this is true or not? If it is true is it as simple as removing the side airbags and reprogramming the computer?

I know this is a 996 forum, but the systems should be identical and so far I got no answers in the other forum. Hopefully someone in here knows a thing or two about this.

This is my dedicated track day toy and it has a full cage. I would like to remove the two side airbags, but for legal reasons (I still need it to be road legal) I need to keep the two front ones. This will be legal because that is how the original car was delivered. Removing the side airbags will help me save a lot of weigth and make it much easier to make lightweight door cards. It will also allow me to keep the front bags without having to worry about the side bars catching and interfering with the side bags if they deploy.

5CHN3LL

I can't answer your question about reprogramming the computer; I can tell you that a number of people have removed the stock steering wheel to replace it with a removable racing wheel but wanted to leave the rest of the SRS system functional.

This is achieved by removing the airbag and using a resistor to provide the correct amount of resistance to "trick" the SRS system into thinking the airbag is still installed; seems to me that this same technique should work for side-impact bags as well.

Here's a thread where the appropriate resistance for the driver-side airbag is discussed; a link to a product that allows you to disable the side-impact bags is linked at the bottom of the thread and might be useful in your situation.

Unsolicited warning: When tinkering with airbags, keep in mind that they are essentially little bombs/shrapnel-less hand grenades full of boron-potassium nitrate which, in addition to rapidly inflating airbags, can be used as a solid rocket engine propellant and other applications where you need something to go "FSSSSSSSSSSSSSSSSSSSSHHH!!!" or "BOOM!!!" Please take the necessary precautions to avoid blowing yourself up, maiming yourself, etc.

bebbetufs

Thanks for your thoughtfull advice and warnings.
My concern is that if there is an investigation after a crash airbags that have been replaced by resistors may be used by the insurance company against me. Reprogramming to the original config would be completely legal.

5CHN3LL

Unless you tell your insurance company that you have modified the supplemental restraint system, regardless of how you effect the change, they're going to take a dim view of any claim you file.

Last time I checked, side-impact airbags are not federally mandated safety devices. If they aren't, defeating them isn't illegal one way and legal the other. If they are, it doesn't matter if you hire the original Porsche software developer to delete them; you've still broken the law.

If you defeat the safety features of your car and subsequently make an insurance claim, your insurer isn't going to care how or why you disabled your airbags.

Or maybe I'm just not comprehending why modifying the system with software vs. modifying the system using hardware - when the net result is identical - would be any more "legal."

bebbetufs

GNorwegian laws are at times incomprehensible, even to us, basically they prohibit modifications. What matters is the modification itself. The point here is that the resistors are a very visible modification, whereas nobody will know with coding because this car's original 97 body only had two airbags. before it was reshelled with a 98 four-bag shell. Recoding returns it to the original configuration and is not considered a modification. Resistors are considered tampering.

5CHN3LL

Oh, jeez - I didn't notice the "Norway" location. I made a xenocentric assumption based on your excellent English (though I realize that ~90% of Norwegians are fluent in both languages); sorry about that.

RE: the dichotomy between an electrical solution vs. a software solution: "The point here is that the resistors are a very visible modification" - I'm not certain I understand the reasoning behind the distinction. Was the car equipped with four airbags when it was delivered? If so, I'm not following the reasoning. Whether the airbags are deleted via software or by installing a resistor, it will also be true that the airbags are going to physically be removed from the vehicle; I'm failing to grasp the subtlety of how it can be legal to remove the airbag one way but not the other.

"whereas nobody will know with coding" suggests that deleting the airbags is the legally questionable act; how you accomplish that deletion seems secondary.

I'm sorry if this comes across as argumentative; feel free to tell me to shove off. I'm genuinely curious, not trying to convince you.

bebbetufs

I appreciate you trying to help. I've decided to go with your advice an use resistors until I can find a way to code the controller. I'm still hoping someone with coding knowledge will chime in.

RE the difference between resistors and software. The car only had 2 airbags when delivered. it was in a crash and was reshelled with a later body that had 4 airbags. I want to return it to the original configuration. The body swap is legal and recorded in the paperwork.

garrett376

On a 996 using a PIWIS2 computer system, there is a section for coding the airbag control unit where no side airbags can be selected, amongst numerous other options.

bebbetufs

Thanks for confirming this.