Need answers on air bag light.
 

I did a search on the air bag dash light. Lot's on seat belt connector but nothing on replacing the control module. Took my box to my Indi today and after hooking up his scanner was given the bad news that I needed a new air bag control module. Apparently it is located under the center console. He needed my vin number to match it up to the right control module. I trust my Indi but is this a part I can purchase from a dimantler or on eBay or should I bite the bullet and purchase new. They want $761.00 for the part and about an hour of labor to install and program. Does this sound about right?
Just looking to be educated here on this problem.

Thanks to all that can give some answers.

Looked at two sources: Auto Atlanta and Pelican Parts and their prices for the control unit at between $710 and $730. Don't know about labor hours, but it sounds in the right ball park. PS: I'm not sure I'd buy a major safety item from a dismantler.

I see the units on eBay for anywhere from $55.00 to $271.00. I agree I don't want to mess around with a safety item, but that is a big difference. My real question is, are these standard units or are they specific to certain model years or vin numbers? If I were to find a low mileage unit, is this a DIY or should this be left to a professional?

If it were me, I'd buy a gently used unit from someone who accepts returns, and DIY the install.

If the unit is bad for whatever reason, it will trigger the same light you have on now and you'll go to plan B, otherwise, you've saved $600 -- for me, no brainer...

If you have a way of checking the used part from junkyard, what's the difference? Around here, they typically give you like 14-30 days warranty for electronic parts.

Check into it yourself to see if you can do it yourself, because for 1hr of work estimated, it's more like 15min of actual work. That's how contracting work, companies tend to over estimate the labor time. As a matter of fact, I have seen that model by popping the plastic side covers off.

Not trying to hijack the thread, but my airbag light sometimes lights up when I turn the key on, most of the times it doesn't. What should be its normal behaviour?

FYI what you are doing can best be described as "Trying to hijack the thread."

Sorry :rolleyes:

Do you have ny idea if I should disconnect the battery before I try an install? If the used unit is good, would it make the light go away or would I still need to hook up a durametric and reset?

Curious what was the initial problem?

I had an air bag light come on a week ago. Diagnosed as an airbag control module gone bad.

What were the codes? The module seldom is the problem.

I didn't see the codes. The Indi said he could not read anything beyond the control module. Apparently it is placed in front of the cars computer and if bad you can't see codes. That is how you determine it is the air bag control module. This is what I am told. That is why I'm posting here to get some clarification before proceeding with a $1000.00 Bill.

I am trying to find out if I can just purchase this module and put it in whiteout reprograming the unit. Someone told me it has to be programmed to my vin number.

The issue can also be grounding and there is a TSB that was posted long ago that covers the repair. Porsche even issued a kit to do the fix.

My '01S had 4 trips to the dealer to get to where the lite was finally off. First two were seat belt, third was grounding, forth was grounding again with me being told that the zone guy had come up with a new procedure beyond the original TSB.

Fault codes for the airbag system can be read by those with the right equipment.

A writeup by Maurice and the original TSB are here.

Make sure your grounding is right before replacing the module.

Always when in for service insist that the codes be given to you. You may do nothing with them but the service tech will think you are watching and checking that what he is trying to sell you on doing makes sense. And posting them enables those on the forums to more accurately focus on what your problem might be.

Thanks for the information. I knew about the seat belt issue and so did my indi when I took it in. Before diagnosing the issue he said it was probably a seat belt latch needing replaced. I did spray electrical contact spray in the latch before taking it to be looked at to no avail. When the indi hooked up his computer to the ODB port, within a minute he said I suspect it is something besides the connector. He said the scan tool would not allow him to "see" beyond the air bag control module to get a code. He said cars are set up like that so that if the control module goes it let you know it by not being able to see beyond the module.

I may take it to the dealer to see if they get the same thing. What I'm really trying to find out is if I buy a "new never used" unit off of ebay, can you plug and play or does it have to be programed for my car? It looks like there is not a lot of information on this here. There are unused units and used units available for much less then the indi is asking. It looks like an easy access and change out if I just knew it could be replaced.

Thanks again for your info.

Can anyone answer if unhooking the battery for awhile and then rehooking back up will hurt anything. I am considering doing this to see if the air bag control module just needs a reset. I know it may be in vain but worth a try. I have the radio code so no issue there.

P.S. I have ordered the control unit from Porsche dealer and will have it installed next week.

I can't answer your last question with 100% certainty, but I would find it shocking is simply disconnecting the battery for a long period, say 20 minutes to an hour, would cause permanent damage. I would think the lack of power may cause some loss of stored data, such as fuel mix settings, but things like these would reset over time and several drive cycles.

It will not reset, so don't bother. You need a PIWIS or Durametric system to reset it.

Thank you JFP. I trust your answers. I will just have to have my indi replace and reset. I did call the dealer to order the part and they needed my VIN number to order the part. It must be specific to the vehicle. Good for furture if someone else is looking for some answers. If this is the case, I still don't understand why people are selling them on ebay for anywhere from $50.00 to $300.00 if you have to reprogram for your car.

It's unclear to me why your indie was not able to read control module codes.

The Porsche 986 diagnostic manual identifies many air bag codes some of which are specific to the module itself. This implies that something can read air bag module codes. Perhaps with Porsche, only the PIWIS can read them. Perhaps other diagnostic computers can read the codes and your independent's cannot.

It would be nice to know because as Mike's note indicates many things can cause the air bag to light to light including grounding issues.