Universal Transmitter
WARNING: This page is about a different car, the 2003 Chrysler Concorde, 2003 Chrysler 300M, 2002 Chrysler Concorde, and 2002 Chrysler 300M. However, it is still accessible from the selected car via links, so may be relevant.
The universal transmitter operates on a non-switched source of battery current so the unit will remain functional, regardless of the ignition switch position.