You need to be sure that the deck supports aux input through IP bus. some dont. If it does than there is some way to turn it on. on my double din you turn the ignition from off to on while holding the number 7 down. then to switch to Aux you press the tape button. If you have the manual you could find out how to do it in there. I have a manual for a deh825 in my car so when i get it back from the shop i will post how to turn it on on that if it helps.