Is it possible to have undercar neons wired so that they flash when you unlock or lock you car? Can you also have them turn on when a door is open on your car?

 

Hook a relay up to use the ground from your interior lights to give your neon a ground thus turning them on..

 

whats a relay what does it do?? thanks

 

A relay allows you to pull a source such as a ground or positive lead and will turn your neon on when the power source is supplied. It's the correct or non-rigged way of doing this. I would use the ground from the door light to feed relay. You need to get a relay and you will see it has 5 prongs on it. I'll tell you how to wire it if you need. Hook your neon up to a fused constant 12 volt and wire your ground to the relay. Everytime your door opens it will supply relay with ground thus grounding neon, turning it on.