for the 2006 model, the steering wheel has audio controls for the OEM audio unit.
If I changed an aftermarket navigation system,
Will I still be able to use those audo control on the steering wheel???

 

that's a noper...there are very few systems out there that can hook up to an OEM controller...

 

what about the pac-swix?

http://www.autotoys.com/x/catalog/UN...WIX_p_597.html

 

There are adapters available. Most likely candidate is something from the PAC line of adapters. A few searches on this board will get you the exact model numbers folks here have used successfully in the past. It may involve soldering resistors to make it work with your Z but I would recomend sending it to a shop to have it done. If it doesnt work you have someone to blame besides yourself.

 

Yes, the SWI-X will let you do that.