your not familiar with the brand ill help you out.
http://www.homelink.com/home/welcome
What Is HomeLink?
HomeLink? is the world?s most widely trusted and used vehicle-based wireless control system. It conveniently and safely enables you to open and close your garage door and front gate, activate and deactivate your home?s security system, and turn on or off your interior and exterior lighting, appliances and electronics. All from three buttons, smartly integrated into your automobile?s interior.
when you have powers seats in the s3 they don't want you to have it installed.
when you have the sports seats it will not be allowed to be installed at the port. when you install at the port there is no installation charge.
when you get it installed afterwards they will charge you an installation charge of 300 or so.
many have theorized why the powered seats disrupts their ability to install the garage door remote as you stated.