I have both Cables. The Cable that came with the radio (Avic-F90bt) Charges the iPhone 3g. However, the video output doesnt work on this cable. With the Apple Composite AV Cable, video Does work. I still get the incompatibility message on the phone with both cables. I am running 2.2.1 firmware on the phone (Jailbroken).
UPDATE (14 April 2009) I noticed yesterday that my iPhone 3G, Running 2.2.1 (Jailbroken) does NOT get a charge while connected to my AVIC-F90BT. Here's what I found...
With the Apple Composite AV Video, while playing music on the iPhone from the Stereo, it doesn't get a charge. Well, if there is any charge, the amount of power required to run the iPhone is greater than the amount of power being supplied to the iPhone via the Apple Composite Video. I didn't NOTICE any change when I left it plugged in for 20 minutes and had the iPhone 3G sitting idle (I.E. it wasnt playing music and the Stereo was in OFF mode).
With the Supplied Cable (the CD-IU230V), it's ALMOST the same as the Apple Cable. While playing music there is no Charge, like the Apple Composite AV cable (read Above). However, when it's in idle mode, it gets a trickle charge. Meaning in the course of 10 minutes, the charge went up 1 %. How could I tell? My phone is jailbroken, and it shows the battery in percentage vice a useless picture of a battery.
Does anyone know of a fix to this? Does anyone know what caused this? Did the iPhone 3G work on past firmware versions?
Theses are my questions, I hope someone has the answers. Smart ass commenters need not reply, this forum has enough of those. It doesn't help anyone if you say "look it up". I carefully research, literally, for hours before I post in a forum. Bring solutions, not problems. If you are going to bring a problem, be detailed in your report so others can help.
Enough ranting, on to the helping.... THANKS!