To my knowledge this was a dealer item only and I found out that there was 3 different ways to install one !! I know as I have one and was having issues with mine and after my dealer fiend looked at mine, there was no way way to turn it off !!!
I have a new Scion RS3200+ security kit, part number 08586-52960, which shows on the box for model year 2004 xB. A web search shows the same part number for a model year 2006 without audio controls on the steering wheel. Please search and verify for yourself this part number matches what you want for your xB.
I am asking $75 including shipping within the 48.
If interested, email me at [email protected], and I will send pictures of the kit along with PDF's of the installation instructions and the operating manual.