I'm completely ignorant here, WHY do you need a car code to use the radio?

Is it like Sirius or something?
Why would it be dysfunctional? Did they change it out before you bought it?

It may be quite possible that there is a series of buttons that you can push
on the front to retrieve the code.
I realize that mine is a lot younger than this but to get my Sirius numbers
all I have to do is push this button at the same time as that button and it
appears on the display.

I say pick up the phone and call your dealership and see if they will tell
you how.

If you really don't want to do that then why not pull the radio out yourself
and get the number off of the back? It's not all that hard to get one out.
Again, any dealership service manager that is worh his salt will help you
figure it out. Explain the WHOLE situation and tell him you want to check
it.

Usually trim just pops off and then you can access the unit. Sometimes you
may need special tools to pull it out but on mine you sure don't.

One other thought.. have you checked the fuse?

K.