Adding a new key?

So I bought one of those ebay flip keys for my 2006 Jetta Wagon TDI (MKIV).

Realized that it didn't have the transponder chop. My key cutting guy (a friendly Popalock) is able to put the SKC and remove and re-register my working flip key. But when I grab an existing used chip from another compatible key, he cannot code it.

It is true that we need to use a virgin transponder? Any idea which one I should buy? Or maybe you have other advice?

Thanks!

Why did you buy another key? If it's to replace an existing one then, I believe*, you can transplant the chip from the old one to the new one.

Not sure if this is doable with 2006s.

You need a chip that is new or previously used on that specific car.

I've noticed there are pages dedicated to all the particulars of adding/replacing keys in these cars. The VAG Tacho is not necessarily required for ever instance. Pretty sure it is if you're adding a key, from what I just read over at MyTurboDiesel they never published them and the dealer can't retrieve.

I am adding a new key. Only have one key right now.

The chips that I was trying to use were used, so I guess that will not work.

Can anyone point me towards the key of chip to buy on ebay? Seems like there are multiple options for frequency.

My locksmith friend can do the programming, I just need to give him the right stuff.

I would do some deep research, maybe you can get new chips?
If you can find one, you just need a new unit with the same number you have, the code and a VCDS.

I have an uncoded rfid chip I can sell you. I'll PM you later tonight.

I don't see why he can't include your key, VCDS would.
When I did have a locksmith do a couple of keys, he had no issues.

Your 2003 will be IMMOB2, OP's 2006 is likely IMMOB3... different set of rules in terms of programming the system.

Any idea what the rules are for an immo3?

Yeah there never was a way to get the SKC to program them -- it's passed directly to the car from VWAG and the only way to do THAT is be a dealer with their interface and software.

With the IMMOB2 cars for a while the SKC was INCLUDED with the owner's packet, and when VWAG stopped (and went to the latter system) the wiley Chinese figured out how to crack it and retrieve it out of the cluster. It's not impossible, incidentally, but the reason the legit vendors won't do it is that it turns out you don't NEED a paired key if you have the SKC -- you can start the car if you can turn the cylinder and on a Kessy system (newer cars with "push button" start) it has to be presumed you could use the SKC without needing to unlock the column mechanically!

This means a tool that can pull SKCs is a very nasty thing indeed as it makes stealing cars a trivial act.

I have the SKC for my 2003 and as such I can program keys using VCDS.... for the newer immobilizer versions I'm not aware of any commonly-available means of getting the pairing code.

The rules for Immo 3 are:

You need the SKC or secret key code. Vag Tacho, which can be rented from FixmyVW.com. will pull that for you.

You will also need VCDS to program the Immo for the new keys. You can program the fob buttons without VCDS.

You need some new keys & fobs.

You need to get the metal keys cut to match the car.

Per the OP's original post, the relevant part I seem to recall that's really different with IMMOB3 is that the chips can only be coded once for any given cluster/SKC

Meaning: an existing chip that's already been coded once can't be re-coded to work with a new SKC.

Or at least I think that's how it works.

Perhaps track down member Jetta 97... he's a local cluster expert.

Yeah, that's the alleged reality, although I've tried to figure out how that would be, since the chip itself is an RFID transponder and has no power in it -- and thus the cluster and ECU have no way to know if some other vehicle matched it in the past (since they can't "see" beyond the vehicle.)

This implies that there's a security fuse in the RFID capsule that gets burnt when it is programmed (e.g. there's a "seed key" sent to it or similar during programming which is a one-time write operation.)

I've never tried programming a key that someone else had used in a different MkIV in the past tho to verify.

I have a key that I'm planning to pair to my car, will let you know how it works after I test it tonight. Immo2 car though, so may not apply to the OP's question.


A new key blade from Fixmyvw was only ~$40 after shipping, and if nothing else would work with a new fob if I have to resort to that.

Edit: post office didn't deliver it for some reason, so the test didn't happen yet. Hopefully today?

I can now confirm that you can pair a used key fob to a new car, assuming that it is Immo2.

I already had the SKC that I retrieved using a VagTacho previously, and was able to follow the VCDS instructions to adapt the anti-theft system to recognize the key.

The key did not work beyond allowing the engine to start, and then immediately shut down when I tested it this morning, but now (after adaptation) it fires up and remains running.

So you may have paired the key but it seems the immobilizer is being activated. Is the light on the dash illuminated?

Uh, no, he said that it DID flag out on initial use, but after being paired it works.

hey_allen said:

I can now confirm that you can pair a used key fob to a new car, assuming that it is Immo2.

Click to expand...

But, Immob 3 /= Immob 2 in this regard, as far as I know.

Maybe. The question is whether there's a way for the actual capsule in the fob to be physically "burned" (e.g. one-time write) that would "mate" it to the ECU and thus prevent re-use.

I guess ping Jetta 97 if you want to know the "why"... here's the "what":

http://forums.tdiclub.com/showpost.php?p=3995865&postcount=6

I understand the statement, but am trying to understand the "why". The ECU has no way to know if the chip in the key has been used before (it has no connection to the outside world) unless the act of pairing it writes a one-time seed key of some sort (in other words, it's a "write once" function.)

Yup... and yet I keep reading words like "alleged" and "maybe".

Again, if you want to know the details behind the system perhaps give the expert a ping. Betcha he can explain it no problem....I for sure dunno. I only weighed in because it looked like the OP was gonna chase his tail trying to re-use an IMMOB3 key.

One thing to note... the ECU does not interrogate the key, the cluster does (at least as far as I know). The cluster than either tells the ECU it's OK to keep running the engine or it's not, and flashes the light while it's at it.

My guess is that the nuance of the IMMOB 3/4 transponder re-use has something to do with how the cluster and fob recognize each other initially... but that's just a guess.

Jetta '97 will know for sure.