I installed this unit yesterday and can't get my iPhone to connect or be seen. It came with the correct cable to allow the advanced app mode but I can't try it as it just will not see the phone. I've checked all the connections and tried connecting the phone to usb2 with another cable which works fine so I know it's not the phone.

Anyone got any ideas?

did you use any extension cords with it? i used an iphone extension and it caused a lot of problems

No, just connected straight to the supplied cable, ca-iw201s is the one that came with it.

Make sure the USB is in the USB1 port, I'm pretty sure the apps will only work if it's setup like that.

I just installed my 8400 tonight and I tested app mode prior to putting everything back together and it was fine. Then I decided to switch my USB cables because I wanted my old iPod video to be USB1 and the phone to be USB2 and now app mode doesn't work.

So I'm going to switch it back tomorrow and see for sure but I'm pretty sure that's your issue.

And in the manual it shows that it needs to be in the bottom USB port. So I know that's my problem and it's probably yours as well...

Nope it was fitted to the bottom usb slot, just couldn't see the phone at all when it was connected. I've sent the cable back to the supplier

This may be as useful as "switch it off and on again" but check your settings on the HU, there is a line that says RGB INPUT and it will either say NAVI or IPOD, if it says Navi it is looking for the add on Nav unit, change it to iPhone/iPod and you'll be up and running.