From reviewing the factory service manual it appears that the climate controlled seats are a completely separate system from the car's climate controls. That portion of the service manual is poorly written - probably a bad english translation - but as best I can tell it's separate. You can read up on it at
http://www.nicoclub.com/FSM/
If I were in your position, I would call Infiniti of Scottsdale and ask if there is more than one part number for the part you need in the '05 model line. You can get their number from their web site at
http://www.everythinginfiniti.com
All of that said, how do you know that you need a new climate control unit?
Heath