hi there, im having probs with my sons radio firstly it says safe when you turn it on, after reading on the internet it says i will need a code for it, but i dont know where it is, help please as i havnt got much of a clue about car radios, or the internet to that point, lol radio model is , gm0200y8331051, if anyone can help i would be eternally greatful, as i dont have the money to take to vauxhall or get a new radio at the moment, thanks