Immobiliser chip ID

[MixerFistit]

I was going to post this in the parts section but didn't want to clutter it as its not really a part number I'm after.

I want to get a new chip for a spare key for my 06 Dispatch.

I've read up on various procedures here but they're all so different from year to year, model to model I thought it best to ask fresh to be on the safe side.

I don't have a BSI, only a CPH. Lexia loads a very basic list on the global test.
The chip I have on my working key is PCF7931AS but I don't know which ID# to order.
I know my 4 digit code for Lexia.
The RCL fob doesn't operate the doors, I've made no attempt to pair it or re-pair it but I know the buttons function and it's likely outputting a signal as I can see the button cell drop a few tenths of a volt when each button is pressed.

So the main question followed by a few others:

1. What ID# transponder do I need?
2. Is there a post with a pairing procedure for my van? Or can someone advise. Does it have to be done when the transponders are cancelled/registered
3. Are there other model key fobs that can be programmed/paired because these side button ones are 'orrible and if I'm going to buy new rubber buttons for £3.50 a pop I may as well buy a tidier fob from an old picasso etc and swap transponders or something.

[wheeler]

If its a mk2 with CPH then you need an ID33 chip for this.
The pairing process is simple & guided with Lexia but all keys need to be deleted & re paired.
The other option is to have the chip cloned, this can be done on an ID33 chip without even needing to be in the car & only takes seconds. You would need the right kit for this or somewhere like timpsons should be able to do it.

[MixerFistit]

Thanks Wheeler. That's good to know. Cloning certainly sounds safer than adding keys (I'm guessing if I somehow mess it up I can retry)
It's a mk2 in lexia terms by which I'd call it a mk1.5 or old shape face-lift 806/synergie type but I'm assuming the newer shapes (807/C8?) don't have a CPH anyway.

Do you know if there's any issues with remote locking pairing on these or is it as simple as clicking buttons as directed to pair the fobs (after pairing the transponders). Eg, they don't need to be virgin fobs like the transponders have to be or anything awkward like that.

And the longest shot of all - can you pair fobs from other vehicles with different fobs? My guess is things aren't as simple as that but it's a nice thought as these side buttons look very fragile..

[wheeler]

To be fair programing keys on these is fairly low risk, if it goes wrong you just start again.
Cloning is ideal if you dont have or cant get the security code as im not aware of any tool that will extract the code on a CPH based system via OBD. The main downside of cloning is if this is your only key and one of the keys is stolen you wouldnt be able to delete that one without getting a brand new chip. If you delete & re add the key that you have back in you also add the clone back in as the chip ID's are the same.
If you have the code & Lexia i would always program fresh chips where possible.
Its a very simple process.
As for re using second hand remotes i believe you can do this but i have never personally tried it myself. The remote programming is also very simple & guided.

[MixerFistit]

A short update, I managed to get the RCL working with lexia. I only have the one key at the moment as I'm still awaiting the second transponder chip but decided to practice. Mine asked me for the remote first then ignition but was a fairly straight forward process.
Regarding the query about other key fobs from other model vehicles. I've read that some fobs are one time only. Am I right in thinking this doesn't apply to the CPH on these vans - but on the flip side am I restricted to only using 433 mhz fobs that also only operate on these CPH units (ie one that operates a BSI wouldn't work?)
I appreciate this is probably in the realm of theory and try it myself lol which I probably will but any input appreciated. Even telling me which vehicles had a CPH would be helpful if that is indeed a restriction

[wheeler]

The Single use type are mainly the remotes that have a built in chip & program at the same time as the transponder.
You can get 'universal' remotes that can be generated to work on hundereds of different cars but have never tested one on a CPH equipped vehicle.
CPH was used on mk2 Xantia, Synergie, Early Xsaras, 306 &probably some other Peugeot models.

[MixerFistit]

Thanks for the info @wheeler

Unfortunately I seem to be having a problem programming the new chip. Should it definitely be Id33?
Lexia seems to be accepting but I think it's just counting the ignition turns rather than verifying a successful write.
My original key still functions and my remote fob also functions (had an error at one point and lost them) so it seems like I'm doing it correctly.

[wheeler]

Some CPH systems used ID48 chips however these are small glass chips, as you said there was writing on the original i would think this was a carbon type chip & would have ruled out it being ID48.
Is the key count showing as 2 after programming?
Is it a genuine Philips chip? any writing on it?
There are types of transponder chips (like king chips or super chips) that can be generated as various different chips, as great as these are i dont find they work very well on older type chips like ID33's & ID40's. I wonder if its one of these? Any writing on the chip should help identify it.
Could just be a dud chip, Where did you buy it?

[MixerFistit]

Ebay but from a store that only deals with that kind of stuff (encloses his auto locksmith business card in the package etc).
The writing is PCF7931AS which matches my original
I've searched previously and seen ID46 can also come in PCF7931AS. I admittedly know little about how these work beyond the basic principles but I assumed PCF7931AS was the basic chip (maybe just the form factor and the ID# was like a sort of firmware layer that can handle certain codes or maybe the internal chip that can handle codes of different complexities. To be fair, the listing doesn't mention Citroën/PSA as compatible, only a few other manufactures. I have seen a few with ID46 for Citroën but they're the later models like Cx vehicles and Dispatch 2007+ so I assumed they were for a more modern system (and of course work through the BSI)

I didn't think to check the other section of lexia for number of keys saved as it was dark and cold so gave up after a few unsuccessful attempts

[MixerFistit]

Most Citroen up to 2001 use an ID33 transponder chip, these are easily cloned by anyone advertising "Chipped" or "Transponder" key cutting.
Citroen from 2001 onwards use mostly ID46 chips (C1 uses ID60),until recently these could not be cloned, they can now be cloned by specialist key cutter or auto locksmiths, usually requiring access to the vehicle.
The Citroen Xantia and Jumper 1999+ use ID60 chips which cannot be 'cloned' yet.

Renault used similar chips at similar times, with the exception of the card system all Renaults can have 'cloned' keys

Peugeot used mostly ID11, ID13, ID33 up until 2001/2002 these can be copied easily, post 2002 some can be 'cloned'

OK I found this old post which suggests ID46 maybe the way forward.

The rest of the post explains how the chips have some bits of data written at the factory and the rest is written by the vehicle once paired. I'm guessing ID46 has a more modern structure to prevent cloning (at the time)

[GiveMeABreak]

If you just want a spare key with integrated chip ready to be programmed to the vehicle, then Citroen still do an uncut key (they no longer supply combination cutting on order given the year).

(4) Lock Key (Uncut), part: 9926GX, £35.26 inc. VAT

This is the spare key non-fob type.

[wheeler]

Most Citroen up to 2001 use an ID33 transponder chip, these are easily cloned by anyone advertising "Chipped" or "Transponder" key cutting.
Citroen from 2001 onwards use mostly ID46 chips (C1 uses ID60),until recently these could not be cloned, they can now be cloned by specialist key cutter or auto locksmiths, usually requiring access to the vehicle.
The Citroen Xantia and Jumper 1999+ use ID60 chips which cannot be 'cloned' yet.

Renault used similar chips at similar times, with the exception of the card system all Renaults can have 'cloned' keys

Peugeot used mostly ID11, ID13, ID33 up until 2001/2002 these can be copied easily, post 2002 some can be 'cloned'

OK I found this old post which suggests ID46 maybe the way forward.

The rest of the post explains how the chips have some bits of data written at the factory and the rest is written by the vehicle once paired. I'm guessing ID46 has a more modern structure to prevent cloning (at the time)

I have read that post & yes it is very out of date but some of it is actually inaccurate too.
I have only ever known CPH based systems to use ID48 or ID33 (ID48 are small glass chips)
Everything i have suggests this is ID33.
A quick google search shows PCF7931 to relate to ID33, when you google it lods of 46's come up but these are usually 7936's.
The other possibility is a failed transponder aerial, i have come across this a few times on early Picassos. The writing part of the coil fails meaning it cant write new chips, As a previously programmed chip does not get written to, when it gets 'deleted' from the system its doesn't actually get deleted it is just blocked by the CPH or BSI, if you 're program' it, all it does it allow it back in.
In this case on the picassos you could just borrow an aerial off another car then swap it back once you have done the programming.

[MixerFistit]

@wheeler That's interesting. Considering at one point the ring was removed from the barrel and wrapped around the original key fob with insulation tape, it's plausible it is damaged in some way.

@GiveMeABreak that's helpful too, didn't think they'd be so cheap. £35 = not messing about.
Would just need to find a key cutter willing then. Last time I took a blank ebay fob into timpsons (flip key upgrade for a xsara picasso) they refused to touch it unless I bought theirs for something like £60 - I walked away and ended up cutting the lease out of my old spare and swapping the blades that way