CalifRay

I recently replaced the battery in my 02 Boxter. Now the radio/nav will not work. It asks for a code which I punched in (as well as the dealer) and it does not work. It does a 60 minute countdown 2 or 3 times and ask for the code again. The dealer pulled the radio/nav unit and checked the serial numbers with Porsche to see if the code was correct, they came up with another code which they said was for the radio and that the nav code does not have to be installed for it to work. I took the code with me while I waited for another 60 minute countdown to complete. I punched in the new code and no luck same results. I am frustrated because the dealer doesn't seem to know what they are doing eighter. Has anyone out there had this problem? Help!!