Remote Control Program for ATMEGA168P circuit
Here's some popular IR codec code for AVR/Arduino:
http://www.righto.com/2009/08/multi-protocol-infrared-remote-library.html
https://github.com/shirriff/Arduino-IRremote

You will need to choose a remote-control, and then program the AVR to do whatever it is you want the car lights to do when you push various remote buttons.