o.k.
So I know this thread is pretty old, but leave it to me to jump on the band wagon late.
I purchased the premium scion radion, three knobs, T1806
I soon realized what I could have figured out, if I just would have read this thread, that's it not all plug and play.
Needless to say, I have all the wires necessary to connect an ipod to this radio and well as the aux port.
After an entire day battling with Toyota about thier Scion wiring harness, and them wanting $1500 for it, I went down to the local salvage/junk yard. There I found a brand new 2007 Tc, with the premium radio.
We opend the center console and pulled the AUX and IPOD harness apart forom the complete dash wiring harness. I paid $75 for both set of cables. The full set that runs from the center console to the back of the T1806 radio.
I went back to Toyota and picked up the Ipod adapter cable for $66, which connects the Ipod to the Scion iPod port.
So now all I have to do plug and play, which will take place on Saturday.
I currently have the old Scion radio (T1804), which I purchased to do a factory SAT setup. Now I will hopefuly have a factory AUX, SAT, and IPOD setup that will work with my steering wheel controls.
I will post picks of all the cables tonight for anyone that is interested.