Rattso

These are what I used to install 2013 HU in my 2008 Scion xB

PT546-74120-MC - microphone w/cable
PT546-00120-CH - 20 pin + 8 pin into 28 pin. Into this goes the mic cable along with the 20 pin plug in Scion.
PT546-00120-AD - antenna adapter. This converts the normal Motorola style barrel connector to the bigger one.

Not sure this is useful to you anymore given it more than 5 months ago that you posted
Maybe someone else will need the info.

I got mine at https://www.toyotapartsdeal.com/
But you can shop around for better prices

Henryt

HI Mr Rattso,
It is amazing to read your post about installation of 2013 HU on 2008 Scion xB. Thank you.
I am doing the same on my 2008 xB. Only 2 connectors 6 pin and 4 pin from xB inserted into the 2013 HU.
The rest are not fit the 2013 HU connectors
Power on, the 2013 HU light up, Bluetooth shows up connects to my cell phone. Problem is NO SOUND!
As you advice, it needs 3 cables PT546-74120-MC, PT546-00120-CH, PT546-00120-AD.
Could you please give me the installation guides and pictures if you can. I appreciate it.
Do I need all those 3 cables and does it compatible with affordable price.
I spent 2 days desperately to look how to solve "no sound" until I read your post. You r a life saver
Thank you,
Henry