Hi there Robin and welcome
you need to go to an Authorized dealer of Pioneer in order to get the code. They need to read information from the unit and from this they can provide the code.
There is no other way to get around this, it is done this way to protect against theft.
If you have any problems, or would like any additional information or assistance, please do not hesitate to let me know.
And if you can take a second to rate my service by clicking one of the stars at the top of the screen then submit, that would be greatly appreciated.