Date registered: Dec 2005
Vehicle: 222.132 & 221.122 & 212.025 & 906.633
Mentioned: 3 Post(s)
Quoted: 35 Post(s)
You would have to follow the advice, wait until the radio requests the security code. I'm afraid you might not have it, do you have all the car documents available, look for a small sticker with 4 or 5 digit code and even better if you can find the radio manual that tells how to enter the code.
If you can't find the code, a dealer should be able to give it to you (against proof of ownership).