I recently had a Scion security system installed on my 2006 tC. I was a little upset to find that the control buttons for the stereo on the steering wheel stopped working after the installation. Toyota service people told me that the factory alarm system were not designed to work with the steering wheel buttons ( they can either connect the alarm system or the buttons but not both) so the bottons will be useless until they come out with a way around it. Anyone know more about this issue???