I would like to replace the CDR23 on my 2005 Cayenne S with a PCM 2.1. I know that I need the PCM 2.1 radio code so that it can be programmed to the vehicle. I called the local dealer and gave them my VIN and serial number of the PCM 2.1 and they gave me a 4 digit code. When my independant connected the vehicle to a PIWIS tester and went to the section to input the code it looks like it needs a much longer code than 4 digits. Does anyone know how long (how many digits or characters) the PCM 2.1 code should be? Or do I need the 4 code digit plus another one? Any help help would be appreciated.