C5 key issues

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jgra1
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C5 key issues

Post by jgra1 »

grr.. chaps I have lost the only key to my old C5 S1 ;(
it was the service key too...
quick question, is it possible to get another service key, or make one.. what I want is a key the is programmed to the car permanently without a battery..
I fear I am asking for the impossible..

many thanks
John

ps I do have the key code, and a key has been programmed to the car before (a button style key, which lost its battery a few months later / or just stopped working after a knock.. I still have that key..
Gibbo2286
Donor 2020
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Re: C5 key issues

Post by Gibbo2286 »

Look up 'Jock the lock' or someone similar in your area. :)

https://www.facebook.com/locksmithscardiff/
jgra1
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Re: C5 key issues

Post by jgra1 »

Thanks gibbo.. but I have lexia and key card so.I was hoping i could do this myself ? :)
I think I can buy a cheap blank key with a chip. Get that chip aligned with car and (in short term) sellotape it to steering column and use an old dead key? A tenner..
Hell Razor5543
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Re: C5 key issues

Post by Hell Razor5543 »

When I got my C5 MK1 it had 2 keys, but one did not have the battery. When I fitted a new battery (a CR2025 IIRC) the key buttons worked straight away. The keys have (in effect) 2 circuits; the circuit for the immobiliser, and the locks. the immobiliser circuit is driven by an inductance circuit, and read from an aerial around the ignition hole.
jgra1
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Re: C5 key issues

Post by jgra1 »

thanks James.. I.am not wortied about central locking .it hasn't ever worked .. I just need a single key with a write once chip (like the service key) so.I can start move and sell car.. the spare key which had a battery lost its connection and a new battery didn't fix that.
The only working key is now missing

I.just want a new simple working key (or to fool.the car into thinking I have one) hence getting a Virgin chip .coding it and leaving it within reach of the aerial ..
I can't really make things any worse so I will proceed with the plan :)
RichardW
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Re: C5 key issues

Post by RichardW »

If the remote key has previously been coded to the car, then it might be possible just to re-introduce it with Lexia and it will work to start the car - worth a try as it costs nothing? Only trouble with taping the key to the immobiliser is that the key in alarm will go off every time you get out the car! I suppose it might work if you just put both keys on a ring - the chip in the other might be near enough to unlock the immobiliser.
jgra1
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Joined: 27 Nov 2005, 20:07
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Re: C5 key issues

Post by jgra1 »

Thanks Richard.. yes could try with old key..
jgra1
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Joined: 27 Nov 2005, 20:07
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Re: C5 key issues

Post by jgra1 »

Have my new key and should be ready to sync with car this evening... is there a buried how to for this job folks? I did watch it being done once but a long time ago
8-[
RichardW
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Re: C5 key issues

Post by RichardW »

Here's one I prepared earlier.....

It's easy enough, no risk of bricking the BSI - you might end up with no working keys though! Plug the lexia in and let it do a global scan. Now go into the BSI, and find key learning. When doing our C4 Picasso, I found it under 'Pack reparation'. Put in the 4 digit confidential code when requested (on a card that was supplied with the car). It will ask you how many keys you want to code - this is the total number, including any that are already coded (you need all the keys you want to be coded, including existing ones). Then just follow the onscreen instructions - put each key in the ignition in turn, and then turn to on till it says coded, then turn off again. Once all coded to the immobiliser, then re-synch any remote locking functions - put the key in, turn on, and press the lock button.

Inevitably you will find the original key tomorrow, but you can re-code that one back in (remembering that you will need to do both).
jgra1
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Joined: 27 Nov 2005, 20:07
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Re: C5 key issues

Post by jgra1 »

many thanks Richard..
only have one key to code, have the 4 digit number..
jgra1
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Joined: 27 Nov 2005, 20:07
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Re: C5 key issues

Post by jgra1 »

done ;) big thanks Richard

one key, albeit without a cut blade, piggybacked onto an old key and went through the process.. failed first 3 times, waited 10 or so minutes and worked on attempt #4 ..car now starts again! will make one key from both, and put the car back up for sale!

J