Security code 406

This is the way to change the code,when you press C for the second time the green lamp should flash 4 times accompanied by 4 beeps to indicate code has been changed. It is possible that the previous owner has put it into the "Service Mode", I do this if I have to leave it for servicing, this mode allows you to put in a second code independent of your personal code, this second code ( it could be 1111 or any other 4 digits) is for the mechanic to use so that you do not have to disclose your real code to him. The only way to reset this is to tap in your real code and this resets the "Service" mode, meaning you can now only use your real code. If this is what has happened you will have to contact the original owner and ask him for this code.

I have a 405 but have not yet attempted to change the original code from when bought - although different from the factory code it still seems a weakness in the system that a "hidden" code can be used to over-ride the immobiliser without the new owners knowledge. Assuming that only the service code has been handed over and not the customer code.

Do Peugeot have any way of resetting the security code if the original code is lost? Or does the ecu have to be changed?

I believe some Auto electricians have the equipment to read the stored code and charge about 60 UKP for doing this. I do not believe the manufacturer offers this service.

Any idea of who might do this? Lucus?

Any info appreciated

manufacturer