I just picked up a z120bt and cannot get it to connect to my iPhone 3GS.
I've got the bluetooth turned on for the Avic, and in the device settings it is identified as "PIONEER NAVI". When I enable bluetooth on the iphone it finds PIONEER NAVI just fine, but when I attempt to connect to it it says "please make sure the device is turned on and enabled". It doesn't even get to the point where it asks me to enter the pairing code.
I can connect to other bluetooth devices with the phone just fine.