Okay, so I got a pretty sweet deal ($30) for the head unit, and yes, I know the connectors are different.
Purchased a used but perfectly working adapter harness set (PT546-00142) which includes the following:

--PT546-00120-CH (20 to 28 Pin Adapter)
--PT546-00120-US (USB Cable)
-PT546-00120-?? (Antenna Adapter)
(converts antenna, another plug, and has a short grey USB adapter) for $50, and aside from needing to purchase the microphone, almost everything works: AM/FM, CD w/ MP3, steering wheel controls.

The short grey adapter takes the proprietary USB plug on the back of the head unit, and provides some sort of female plug (which I will refer to as USB1) and ultimately winds up at the USB port. I am not sure exactly what I need.
Is there a whole other pricey harness, or is there a simple cable that goes from a Scion USB port to the female connector?

There is a "mystery" connector on my adapter harness set which *might* also be related to USB (which I will call MYSTERY1 until I know more). Is this the same as on a Scion USB port?

Finally there is one plug on the factory harness that doesn't fit anywhere - the male connector that plugs into the bottom of the old T1808 underneath the other two connectors on the passenger side.
I'm guessing that is for the 30 pin Apple iPod (pre-Lightning) and AUX connectors inside the center console, neither of which I am using. Can anyone confirm this? It's a wide and narrow connector.

Overall, I am happy with the upgrade so far, and look forward to acquiring the microphone for Bluetooth enablement and figuring out the rest of the USB port.

Any input would be helpful...Thanks!



Name: USB1 Connector. This is from PT546-00140-US. How do I go from this to a USB port?



Name: MYSTERY1 Connector. I believe some factory Scion USB ports have the same connector. Do I need to do something with this for enabling USB music playback?

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