My fear would be the ipod wont talk to it, unless its a really old ipod. Mine (07 i think) has a 12v connection, so you need to buy a 5V adapter for any of the more recent even 30 pin ipods, so thats step one.
I doubt the harness changed from 07-09. I would just be wary that the firmware on the ipod is too new, IF its a 30 pin, mine doesnt like anything with a lightning port even with the official apple adapter.