C4 Fob Programming

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Re: Do you use lexia to program the key fob(remote)

Post by Ramc4 » 08 Nov 2019, 17:02

Paul-R wrote:
08 Nov 2019, 16:13
If I understand correctly I believe that locksmiths go down a different route and clone a key rather than pair a new one in. How they do that if there's no key at all I don't know.
You can use a lockpick like lishi to decode the lock and you also get handheld key cutters such as a1 pak a punch. So you can get in and also carry a range of transponders however you won't be able to program any keys without the security. However you can directly read the eeprom on the ecu by either soldering wires or using a clip and attaching this to laptop.

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Re: Do you use lexia to program the key fob(remote)

Post by GiveMeABreak » 08 Nov 2019, 17:33

Ramc4 wrote:
08 Nov 2019, 14:03
Just out of interest, would a pro locksmith ever attempt to decrypt the security code from the eeprom by dumping the memory while out on a job?

Say a mobile locksmith was called out and the customer had lost their there but badly needed the car, you can decode and cut a key on the spot but can't program without the code but you can decrypt the code from a memory dump. So would this just be too unorthodox a thing to do on a callout?
On some systems the code is encrypted and so not a matter of extracting it as it would be useless. Others 'clone' a key from working one. But in all cases new fobs / keys need to be coded to the vehicle using a suitable diagnostic tool. The code cannot normally be dumped from the BSI without first removing and connecting up to the BSI using special software and hardware - so no - that is unlikely to be the case. They are more likely to obtain the code after you provide them with the same identity check and ownership evidence that a dealer would request from you and then they can code a key with your confidential key.