Lexia 3 programming key.

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olgo57
Posts: 1
Joined: 09 Apr 2026, 20:10

Lexia 3 programming key.

Unread post by olgo57 »

Hi! I have had my ignition lock go bad so I bought a used one from the junk yard to My Citroen C5 from 2006. That is now mounted in the car and with it was one key that works the lock. I can start the car by holding the old key at the ignition lock and start.
I have tried to program the key that went with the used lock wit diagbox (lexia3 for my old citroen) but it refuses to program the key. There is no problem talking to the car and read fault codes under lexia 3, so communication is good.
Seen this done in youtube on an C5 my age so it should work.
Why will it not program the key? I have the right PIN code so that is not a problem.
Best regards Olof.
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Paul-R
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Joined: 07 May 2009, 16:24
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Re: Lexia 3 programming key.

Unread post by Paul-R »

The chip inside is single programmable only. Your simplest option is to swap the blades over on the two key fobs. Make sure you keep the old one as the blade will still fit the doors even though it won't start the car.
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