while theoretically possible, im pretty sure this wont work. its not the lights on top of emergency vehicles that trip the sensor, its an infrared strobe. and while there is a very slim chance that you may be able to get your remote to put out the right frequency, the odds of that coupled with it being bright enough to be picked up are extremely small. if you actually wanna do this (and it is highly illegal), search around for infrared led tutorials, i've seen several explaining how to make one of these for real.
and just a fun little tid bit, point your camera on your phone at the end of a tv remote and press a button on the remote, and you can see the infrared signal, even though you cant see it with the naked eye