Heads up... I got my new IPhone 6 Plus on Friday and it doesn't work on my Z120. I've been using the lighting adapter to convert the interface when I upgraded from my iPhone 4 to the 5 and everything was working OK.

The head unit won't even recognize there's a phone connected now.

In another thread the poster was advised by Pioneer to do a factory reset on his Z130BT, and that worked. So check that your settings that you like are written down and give it a try.

I did a factory reset...and it didn't fix the issue

I've been out of the loop on this forum.  I got my iPhone 6 today and plugged up to my Z120bt.  It recognizes the phone, charges and I'm able to play/browse my music.  It doesn't play videos but I haven't had that feature for some time.  I haven't done any type of firmware update for at least 2 years.  I don't know what version I'm running.  I can check later, but for the most part everything looks like it runs the same as it did with my iPhone 5.  I have the lightning adapter on my original pioneer cable.