This is for anyone who is planning on or has swapped their radio AND the display to get around the coding issue. I have just had a radio programmed and was told what happens if you do it this way.
If you swap the radio and the display together the radio will work. However if you ever have a fault and need another part coding it will come up as unmatching security codes in the car (the radio, dash, engine ecu, all of them etc all need to match). Whilst a good tech 2 guy can get around it by returning all ecus to the factory setting and starting from scratch, it is not what you want to be doing. It will take A LOT longer and will occur you substantial extra cost because of the time involved. Many garages will not be able to program your car.
I am not suggesting you do not swap your radio this way, it is an easy way of swapping your radio to a better or different one. What I am sugestting is that if you do, keep your old radio and display to swap back if you want some coding work done.
I am interested in what the tech 2 experts on here think of this and if they can back it up. However, I had an uncoded radio which needed programing anyway so the guy had no reason to lie to me about what happens if I had just got the matching display. We were just talking.
Also if you do not have the original radio I am not sure what happens if you just remove the radio and display when you code the car, i believe that might work too. I just think it might be advisable to keep your old unit instead of selling it one, just in case. It may be cheaper in the long run!!