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Option Questions

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I was curious so I downloaded the list of options from elsewhere on the site and checked against my sticker under the hood. There are a couple that weren't in the list and I thought I'd just ask.

These weren't listed:




Any ideas?

Also, it lists option 224 - ABD (active break differential), what does this do?



'99 c2

Edited by ekename
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Loren and all:

If I understand your note correctly, can one assume that ANY MY'99 C2 with TC would also have LSD?

My recently purchased '99 does have TC. Jacked up the rear of the car to see if the rear wheels moved together as other cars I've had with LSD. When turning one wheel the other does not move at all.



222 - Traction Control

224 - Limited Slip Differential

448 - perhaps 446 - Carrera concave trim center hubs

880 - perhaps 680 - Sound System (for MY99 this meant amp)

In MY99 TC and LSD were an option. Always sold together they performed a similar function to PSM.

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I have never seen a MY99 with TC that did not have LSD (not to say it isn't possible). Check you option codes for M220 or M224. If you don't have the codes you can get a certificate of authenticity from PCNA that will show all of your cars' original options.

The LSD on a MY99 is only 40%. From the tech manual:

To get the engine’s power safely to the road in a standing start, slip is limited to 40 percent. Once under power, the slip factor changes to 60 percent because the engine no longer is operating at its maximum torque and also because this configuration helps minimize oversteer under load changes through a turn.
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Is there any way to check on the car itself for the existence of a LSD. My car is a little bit of a challenge. Some previous owner removed the option code sticker (there is still residue on the underside of the lid). I've had a dealer and PCNA both check their listing of option codes for my VIN and while most of the options they list DO match my car, they are not a perfect match.

Their records show P72 which I think is a design package, tiptronic only (my car is a 6spd)

My car clearly has Traction control, but no option 222 listed

They also list X369, which I haven't been able to find listed anywhere.

If I pay the $$'s to PCNA for a Certificate of Authenticity, does the information come from this same database, or is there any chance it is generated off another database which may be more accurate?

Is there any way to check the car directly for a LSD? My standard check doesn't conform with previous experience with LSD OR Open Diff. (With both rear wheels in the air and the car in neutral, I can spin either rear wheel manually and the opposite wheel doesn't move at all.)

Thanks for the feedback!


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Well, some options could have been added after the car was delivered. For instance my car was delivered without Litronics or a CD Changer - I added both (factory parts). The Certificate of Authenticity is good and likely worth the money if you want to prove what was originally delivered with the car. I have one for my car.

If you can look at your transmission while it is on a lift sometime try and find the part number. A LSD transmission has a part number like 996 300 020 xx. A normal transmission (from MY99) would be 996 300 010 xx.

P72? P72 hasn't been used since the early nineties (as I recall). There is an X72 which is a walnut and aluminum shift knob.

X369? how about M369 comfort seats?

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Thanks for taking a shot Loren. I continue to be perplexed though. I can't imagine that anyone would go through the work of fitting TC to a non-TC car. My car also has an aerokit, which I'd definitely assume was added by the dealer. Almost all the options, even ones that are pretty easy to change (CF parts, alum. dials, wheels, Xenons, Headlight washers, CD changer) correspond to the Porsche list.

Porsche correctly lists Y05 for my car- Carbon/Aluminum brake & shifter handles

They also correctly list P15 full power seats.

Based upon these items being correct, I think it's unlikely that the car ever had comfort seats(heated w/lumbar adj??) or walnut/alum shift knob.

I'll put the car in the air and check for the transmission PN. If you have a chance, could you specify where to look? My old 944 had it at the very top and was almost impossible to see with the transaxle mounted in the car.

Thanks again Loren. I'm very thankful for the time and effort you're putting into this website to help so many of us.

Edited by jrothma
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  • 3 weeks later...
222 - Traction Control

224 - Limited Slip Differential

448 - perhaps 446 - Carrera concave trim center hubs

880 - perhaps 680 - Sound System (for MY99 this meant amp)

In MY99 TC and LSD were an option. Always sold together they performed a similar function to PSM.


1st, thanks for the site. What a great resource.:notworthy:

2nd, my US '99 996 coupe tip has option codes 222, 224 and 234, among others. 222 is Traction Control. I've seen 224 described as Active Brake Diff and yet you call it Limited Slip Diff. They're different I think, in that ABD is an e-version of LSD...maybe.

Is 234 related? I can't find that option code anywhere.

I'd love to gain a better understanding of how TC, ABD and LSD work together, and if my car, one month new to me, has all three.



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I do not know everything about the early options and TC was only around for the C2 in MY99. Traction Control (TC) is a combination of anti-slip control (ASR) and Automatic Brake Differential (ABD). TC prevents spinning of the drive wheels when moving off and accelerating. It does this through a series of sensors (also used by the ABS system) and controlling individual wheel braking. By doing so driving stability and traction are improved over the entire speed range. PSM includes the functions: ABS, Traction Control (TC), ABD, MSR (engine drag torque control). ABD is part of TC and to my knowledge was not sold separately - together they formed the early version of PSM.

The official name (in the Porsche parts list) for option 224 is "Automatic Limited Slip Differential". There are no parts in the parts list that identify with a M 224 label - so what is it? ABD? maybe?

Technically the option 220 "Locking Differential 40%" is also "automatic" since the multiple-disc limited-slip differential causes locking when one wheel begins to slip. This is the mechanical LSD we all know.

I can not find an option 234 listed anywhere.

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