Universal Transmitter
WARNING: This page is about a different car, the 2004 Lincoln LS. However, it is still accessible from the selected car via links, so may be relevant.
The HomeLink® universal transmitter is an integral part of the left hand sun visor assembly. This universal transmitter provides a convenient way to substitute up to three hand-held transmitters with a single built-in device. The transmitter will learn the radio frequency codes of most current transmitters to operate garage doors, entry gates, security systems, and home or office lighting.